Biopharmaceutics of phenylpropanolamine
- Authors: Dowse, Roslind
- Date: 1984
- Subjects: Biopharmaceutics Pharmacokinetics Phenylpropanolamine Pharmacology High performance liquid chromatography
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3818 , http://hdl.handle.net/10962/d1004915
- Description: Phenylpropanolamine (PPA), a sympathomimetic amine, has been widely used over the past 40 years as a decongestant and, in much larger dosages, as an appetite suppressant. Considerable interest has recently been shown in this drug due to its increasing popularity as an over-the-counter anorectic agent. Much controversy exists concerning the unfavourable side-effects of PPA resulting from the higher doses required for appetite suppression and the potential of this drug for abuse. A literature search revealed a paucity of information concerning the determination of PPA in biological fluids and, most noticeably, on the pharmacokinetics of this drug. An original method for determining PPA in serum and urine using high performance liquid chromatography (HPLC) which has increased sensitivity over other published HPLC methods is presented here. The simplicity of the extraction from biological fluids and subsequent determination by HPLC, enables concentrations of PPA to be monitored after a single dose of the drug. This method is therefore readily applicable to bioavailability and pharmacokinetic studies. The dissolution profiles of 4 sustained-release formulations of PPA were determined in a modified USP rotating paddle apparatus and the samples analysed using HPLC. A mathematical equation was applied to these data which are expressed in terms of dissolution parameters. Oral test dosage forms and solutions of PPA were investigated in bioavailability trials using the developed HPLC method to analyse the urine and serum samples. Linear one body compartment kinetics were assumed and the WagnerNelson method used to transform in vivo serum data to absorption plots which were then fitted to the well known Weibull equation. In order to more appropriately characterize the kinetic processes of absorption, distribution and elimination, a more complex model was utilized which involved numerical integration of a series of differential equations. The data were fitted to these models using nonlinear regression techniques. The pharmacokinetics of PPA are shown to exhibit some evidence of nonlinearity. The absorption of the drug appears to be di scontinuous and PPA seems to favour a two body compartment model.
- Full Text:
- Date Issued: 1984
- Authors: Dowse, Roslind
- Date: 1984
- Subjects: Biopharmaceutics Pharmacokinetics Phenylpropanolamine Pharmacology High performance liquid chromatography
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3818 , http://hdl.handle.net/10962/d1004915
- Description: Phenylpropanolamine (PPA), a sympathomimetic amine, has been widely used over the past 40 years as a decongestant and, in much larger dosages, as an appetite suppressant. Considerable interest has recently been shown in this drug due to its increasing popularity as an over-the-counter anorectic agent. Much controversy exists concerning the unfavourable side-effects of PPA resulting from the higher doses required for appetite suppression and the potential of this drug for abuse. A literature search revealed a paucity of information concerning the determination of PPA in biological fluids and, most noticeably, on the pharmacokinetics of this drug. An original method for determining PPA in serum and urine using high performance liquid chromatography (HPLC) which has increased sensitivity over other published HPLC methods is presented here. The simplicity of the extraction from biological fluids and subsequent determination by HPLC, enables concentrations of PPA to be monitored after a single dose of the drug. This method is therefore readily applicable to bioavailability and pharmacokinetic studies. The dissolution profiles of 4 sustained-release formulations of PPA were determined in a modified USP rotating paddle apparatus and the samples analysed using HPLC. A mathematical equation was applied to these data which are expressed in terms of dissolution parameters. Oral test dosage forms and solutions of PPA were investigated in bioavailability trials using the developed HPLC method to analyse the urine and serum samples. Linear one body compartment kinetics were assumed and the WagnerNelson method used to transform in vivo serum data to absorption plots which were then fitted to the well known Weibull equation. In order to more appropriately characterize the kinetic processes of absorption, distribution and elimination, a more complex model was utilized which involved numerical integration of a series of differential equations. The data were fitted to these models using nonlinear regression techniques. The pharmacokinetics of PPA are shown to exhibit some evidence of nonlinearity. The absorption of the drug appears to be di scontinuous and PPA seems to favour a two body compartment model.
- Full Text:
- Date Issued: 1984
Health literacy assessment: relexicalising a US test for a South African population
- Hunt, Sally, Dowse, Roslind, La Rose, Christopher M
- Authors: Hunt, Sally , Dowse, Roslind , La Rose, Christopher M
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/139131 , vital:37708 , DOI: 10.2989/SALALS.2008.26.2.7.571
- Description: The problems of illiteracy in health contexts have been well documented in the literature and include such serious repercussions as medication non-compliance and failure to seek medical help during the course of an illness. The Rapid Estimate of Adult Literacy in Medicine (REALM) is a standardised health literacy test developed in the United States that has been previously administered and researched in South Africa (Lecoko, 2000). It is an objective vocabulary test, designed as a screening instrument to identify the health literacy levels of patients in clinics, which uses item recognition of 66 health-related words. Lecoko found that, in a South African setting, only 8 out of the 66 words in the US-developed test could be deemed acceptable. Therefore, the current study focused on the principled relexicalisation of the REALM, using words gathered from health information and promotional texts in local clinics, hypothesising that this would improve its applicability. After administration to a statistically similar group of respondents, the number of acceptable words on the test increased from eight to 38. Thus it is concluded that principled relexicalisation may be one way of improving the applicability of standardised health literacy tests to local populations and settings. However, the limitations of standardised tests may prove to be a significant barrier overshadowing the value of relexicalisation.
- Full Text:
- Date Issued: 2009
- Authors: Hunt, Sally , Dowse, Roslind , La Rose, Christopher M
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/139131 , vital:37708 , DOI: 10.2989/SALALS.2008.26.2.7.571
- Description: The problems of illiteracy in health contexts have been well documented in the literature and include such serious repercussions as medication non-compliance and failure to seek medical help during the course of an illness. The Rapid Estimate of Adult Literacy in Medicine (REALM) is a standardised health literacy test developed in the United States that has been previously administered and researched in South Africa (Lecoko, 2000). It is an objective vocabulary test, designed as a screening instrument to identify the health literacy levels of patients in clinics, which uses item recognition of 66 health-related words. Lecoko found that, in a South African setting, only 8 out of the 66 words in the US-developed test could be deemed acceptable. Therefore, the current study focused on the principled relexicalisation of the REALM, using words gathered from health information and promotional texts in local clinics, hypothesising that this would improve its applicability. After administration to a statistically similar group of respondents, the number of acceptable words on the test increased from eight to 38. Thus it is concluded that principled relexicalisation may be one way of improving the applicability of standardised health literacy tests to local populations and settings. However, the limitations of standardised tests may prove to be a significant barrier overshadowing the value of relexicalisation.
- Full Text:
- Date Issued: 2009
Pharmaceutical Pictograms: part 2: weird and wonderful interpretations
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157037 , vital:40081
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157037 , vital:40081
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
In vitro release of amoxycillin from lipophilic suppositories
- Webster, Jessica A, Dowse, Roslind, Walker, Roderick B
- Authors: Webster, Jessica A , Dowse, Roslind , Walker, Roderick B
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184377 , vital:44213 , xlink:href="https://doi.org/10.3109/03639049809085636"
- Description: The in vitro release characteristics of amoxycillin from different lipophilic suppository bases were investigated using the USP rotating basket method. Suppositories containing 250 mg amoxycillin were prepared in theobroma oil and in the semisynthetic bases Witepsol W35, Suppocire A32, Novata BD, and Novata 299. Both freshly prepared and 1-month-old suppositories were tested. Analysis of amoxycillin was performed using a validated high-performance liquid chromatographic (HPLC) technique. Release profiles differed significantly between bases, with the greatest amount of amoxycillin being released from both newly made and 1-month-old Novata BD bases (87.57 ± 8.18 and 99.66 ± 6.63%, respectively), and the lowest amount released from the newly manufactured theobroma suppositories (8.82 ± 0.75%) and the 1-month-old Suppocire A32 suppositories (7.78 ± 0.27%).
- Full Text:
- Date Issued: 1998
- Authors: Webster, Jessica A , Dowse, Roslind , Walker, Roderick B
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184377 , vital:44213 , xlink:href="https://doi.org/10.3109/03639049809085636"
- Description: The in vitro release characteristics of amoxycillin from different lipophilic suppository bases were investigated using the USP rotating basket method. Suppositories containing 250 mg amoxycillin were prepared in theobroma oil and in the semisynthetic bases Witepsol W35, Suppocire A32, Novata BD, and Novata 299. Both freshly prepared and 1-month-old suppositories were tested. Analysis of amoxycillin was performed using a validated high-performance liquid chromatographic (HPLC) technique. Release profiles differed significantly between bases, with the greatest amount of amoxycillin being released from both newly made and 1-month-old Novata BD bases (87.57 ± 8.18 and 99.66 ± 6.63%, respectively), and the lowest amount released from the newly manufactured theobroma suppositories (8.82 ± 0.75%) and the 1-month-old Suppocire A32 suppositories (7.78 ± 0.27%).
- Full Text:
- Date Issued: 1998
The evaluation of pharmaceutical pictograms in a low-literate South African population
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6362 , http://hdl.handle.net/10962/d1006058
- Description: An inability to read and understand written medication instructions may be a major contributory factor to non-compliance in certain patient populations, particularly in countries with a high illiteracy rate such as South Africa. Twenty three pictograms from the USP-DI and a corresponding set of 23 locally developed, culturally sensitive pictograms for conveying medication instructions were evaluated in 46 Xhosa respondents who had attended school for a maximum of 7 years. Respondents were tested for their interpretation of all 46 pictograms at the first interview and again 3 weeks later. The correct meaning of each pictogram was explained at the end of the first interview. Preference for either the Local or USP pictograms was determined. At the follow-up interview, 20 of the Local pictograms complied with the ANSI criterion of ≥85% comprehension, compared with 11 of the USP pictograms. Respondents indicated an overwhelming preference for the Local pictograms.
- Full Text:
- Date Issued: 2001
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6362 , http://hdl.handle.net/10962/d1006058
- Description: An inability to read and understand written medication instructions may be a major contributory factor to non-compliance in certain patient populations, particularly in countries with a high illiteracy rate such as South Africa. Twenty three pictograms from the USP-DI and a corresponding set of 23 locally developed, culturally sensitive pictograms for conveying medication instructions were evaluated in 46 Xhosa respondents who had attended school for a maximum of 7 years. Respondents were tested for their interpretation of all 46 pictograms at the first interview and again 3 weeks later. The correct meaning of each pictogram was explained at the end of the first interview. Preference for either the Local or USP pictograms was determined. At the follow-up interview, 20 of the Local pictograms complied with the ANSI criterion of ≥85% comprehension, compared with 11 of the USP pictograms. Respondents indicated an overwhelming preference for the Local pictograms.
- Full Text:
- Date Issued: 2001
Pictograms in pharmacy:
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 1998
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157048 , vital:40082 , https://0-doi.org.wam.seals.ac.za/10.1111/j.2042-7174.1998.tb00924.x
- Description: This review examines the use of pictograms in health care. Well designed pictograms are simple, clear, graphic symbols able to convey their intended meaning to all patients, including those who are illiterate, elderly or visually impaired. Although some research on the effectiveness of pictograms has not supported the hypothesis that pictograms are beneficial for the acquisition and comprehension of information, most studies investigating health‐related applications of pictograms have shown them to be of benefit in the comprehension and recall of instructions on prescription and over‐the‐counter medicines. However, the success of pictograms as a communication aid in pharmacy depends first on a rigorous design process, followed by well‐designed, randomised, controlled trials using an appropriate method of evaluation. The final stage is to investigate the optimal way of using pictograms in practice and to assess their effect on behavioural outcomes, such as compliance.
- Full Text:
- Date Issued: 1998
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 1998
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157048 , vital:40082 , https://0-doi.org.wam.seals.ac.za/10.1111/j.2042-7174.1998.tb00924.x
- Description: This review examines the use of pictograms in health care. Well designed pictograms are simple, clear, graphic symbols able to convey their intended meaning to all patients, including those who are illiterate, elderly or visually impaired. Although some research on the effectiveness of pictograms has not supported the hypothesis that pictograms are beneficial for the acquisition and comprehension of information, most studies investigating health‐related applications of pictograms have shown them to be of benefit in the comprehension and recall of instructions on prescription and over‐the‐counter medicines. However, the success of pictograms as a communication aid in pharmacy depends first on a rigorous design process, followed by well‐designed, randomised, controlled trials using an appropriate method of evaluation. The final stage is to investigate the optimal way of using pictograms in practice and to assess their effect on behavioural outcomes, such as compliance.
- Full Text:
- Date Issued: 1998
Using visuals to communicate medicine information to patients with low literacy:
- Authors: Dowse, Roslind
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156958 , vital:40073 , https://journals.sagepub.com/doi/pdf/10.1177/104515950401500106
- Description: The patient was adamant that she had taken her medicine as instructed, pointing to the visual (Visual 1) illustrating the instructions to endorse this. Via an interpreter, she communicated that she took her tablet three times during the day and once at night (which was correct), but only on those days when the sun was shining (not on cloudy days) and the moon was visible (depending on both cloud cover and phases of the moon).
- Full Text:
- Date Issued: 2004
- Authors: Dowse, Roslind
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156958 , vital:40073 , https://journals.sagepub.com/doi/pdf/10.1177/104515950401500106
- Description: The patient was adamant that she had taken her medicine as instructed, pointing to the visual (Visual 1) illustrating the instructions to endorse this. Via an interpreter, she communicated that she took her tablet three times during the day and once at night (which was correct), but only on those days when the sun was shining (not on cloudy days) and the moon was visible (depending on both cloud cover and phases of the moon).
- Full Text:
- Date Issued: 2004
Pictograms for conveying medicine instructions: comprehension in various South African language groups
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6354 , http://hdl.handle.net/10962/d1006038
- Description: The comprehension of medicine instructions is essential for the safe and effective use of medicines. In cases where low literacy constitutes a possible barrier to understanding written medicine information fully, the inclusion of pictograms may facilitate comprehension. Twenty-three internationally available pictograms and 23 corresponding locally developed images were evaluated in 304 low-literate respondents from eight different South African language groups. Demographic data were collected and an English literacy test was administered to those respondents who had stated that they could read English. Interviewees were shown the 46 pictograms in random order and were asked for their interpretation. Preference for either the international or local version was assessed. Correct interpretation of individual pictograms ranged from 14% to 97%. Images which had been developed locally were more successful in eliciting correct interpretations than those obtained from an international source (USP pictograms). Only 2 of the 23 USP pictograms achieved the 85% criterion of the American National Standards Institute compared with 12 of 23 locally developed counterparts. Local pictograms were preferred over the American ones in all cases. Standard of education had a significant influence on interpretation, whereas no significant differences in interpretation could be attributed to cultural diversity between the African language groups. Almost all respondents (98%) reacted positively to the idea of having pictograms on their medicine labels. The success of the local pictograms highlighted the value of a rigorous and consultative design and test process. Results from one African language group can reliably be extrapolated to other groups in South Africa.
- Full Text:
- Date Issued: 2004
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6354 , http://hdl.handle.net/10962/d1006038
- Description: The comprehension of medicine instructions is essential for the safe and effective use of medicines. In cases where low literacy constitutes a possible barrier to understanding written medicine information fully, the inclusion of pictograms may facilitate comprehension. Twenty-three internationally available pictograms and 23 corresponding locally developed images were evaluated in 304 low-literate respondents from eight different South African language groups. Demographic data were collected and an English literacy test was administered to those respondents who had stated that they could read English. Interviewees were shown the 46 pictograms in random order and were asked for their interpretation. Preference for either the international or local version was assessed. Correct interpretation of individual pictograms ranged from 14% to 97%. Images which had been developed locally were more successful in eliciting correct interpretations than those obtained from an international source (USP pictograms). Only 2 of the 23 USP pictograms achieved the 85% criterion of the American National Standards Institute compared with 12 of 23 locally developed counterparts. Local pictograms were preferred over the American ones in all cases. Standard of education had a significant influence on interpretation, whereas no significant differences in interpretation could be attributed to cultural diversity between the African language groups. Almost all respondents (98%) reacted positively to the idea of having pictograms on their medicine labels. The success of the local pictograms highlighted the value of a rigorous and consultative design and test process. Results from one African language group can reliably be extrapolated to other groups in South Africa.
- Full Text:
- Date Issued: 2004
Pharmaceutical Pictograms: Part 1: Communicating Medicine Information to the Low-literate Patient
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157026 , vital:40080
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157026 , vital:40080
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
The influence of education on the interpretation of pharmaceutical pictograms for communicating medicine instructions:
- Dowse, Roslind, Ehlers, Martina S
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157014 , vital:40079 , DOI 10.1211/002235702810
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
- Authors: Dowse, Roslind , Ehlers, Martina S
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157014 , vital:40079 , DOI 10.1211/002235702810
- Description: To assess the influence of formal education on the interpretation of pharmaceutical pictograms.
- Full Text:
- Date Issued: 2003
Suppositories: An underutilized dosage form
- Webster, Jessica A, Dowse, Roslind, Walker, Roderick B
- Authors: Webster, Jessica A , Dowse, Roslind , Walker, Roderick B
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184697 , vital:44264 , xlink:href="https://hdl.handle.net/10520/AJA16836707_911"
- Description: The rectal route is useful for the delivery of both local acting and systemic drugs. In certain cases suppositories are the best form of therapy, or else they are an effective alternative when oral therapy is not possible. However; doctors rarely prescribe them and patients are often reluctant to use them. Understanding how suppositories work, and their numerous uses, can overcome the aversion to this particular dosage form. Pharmacists are in an ideal position to educate doctors, other health care providers, and patients, on the benefits of using suppositories and their correct use, and to offer advice on any problems associated with their use.
- Full Text:
- Date Issued: 1996
- Authors: Webster, Jessica A , Dowse, Roslind , Walker, Roderick B
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184697 , vital:44264 , xlink:href="https://hdl.handle.net/10520/AJA16836707_911"
- Description: The rectal route is useful for the delivery of both local acting and systemic drugs. In certain cases suppositories are the best form of therapy, or else they are an effective alternative when oral therapy is not possible. However; doctors rarely prescribe them and patients are often reluctant to use them. Understanding how suppositories work, and their numerous uses, can overcome the aversion to this particular dosage form. Pharmacists are in an ideal position to educate doctors, other health care providers, and patients, on the benefits of using suppositories and their correct use, and to offer advice on any problems associated with their use.
- Full Text:
- Date Issued: 1996
Effect of pictograms on readability of patient information materials:
- Mansoor, Leila E, Dowse, Roslind
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157003 , vital:40078 , https://0-doi.org.wam.seals.ac.za/10.1345/aph.1C449
- Description: To design, develop, and evaluate a simple, understandable medicine label and patient information leaflet (PIL) for nystatin suspension, and to assess the effect of incorporating pictograms on understanding in low-literate participants.
- Full Text:
- Date Issued: 2003
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2003
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157003 , vital:40078 , https://0-doi.org.wam.seals.ac.za/10.1345/aph.1C449
- Description: To design, develop, and evaluate a simple, understandable medicine label and patient information leaflet (PIL) for nystatin suspension, and to assess the effect of incorporating pictograms on understanding in low-literate participants.
- Full Text:
- Date Issued: 2003
Pharmacokinetics of phenylpropanolamine in humans after a single dose study
- Dowse, Roslind, Haigh, John M, Kanfer, Isadore
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1987
- Language: English
- Type: Article
- Identifier: vital:6363 , http://hdl.handle.net/10962/d1006059
- Description: The pharmacokinetics of phenylpropanolamine have been studied in healthy human volunteers following the oral administration of an aqueous solution of the drug (50 mg/200 ml). Blood and urine samples collected throughout the trial were assayed using HPLC with UV detection. The drug was shown to be rapidly absorbed with a mean tmax of 1.47 ± 0.49 h and a mean elimination half-life of 4.0 ± 0.5 h. Phenylpropanolamine is predominantly excreted via the kidney with a mean renal clearance of 0.646 ± 0.089 liter/kg/h and 90.2 ± 1.7% excreted unchanged in the urine. The data were not well described using conventional one or two body compartment models. However, the incorporation of a discontinuous absorption phase into the models resulted in an improved overall fit with better characterisation of the absorption phase.
- Full Text:
- Date Issued: 1987
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1987
- Language: English
- Type: Article
- Identifier: vital:6363 , http://hdl.handle.net/10962/d1006059
- Description: The pharmacokinetics of phenylpropanolamine have been studied in healthy human volunteers following the oral administration of an aqueous solution of the drug (50 mg/200 ml). Blood and urine samples collected throughout the trial were assayed using HPLC with UV detection. The drug was shown to be rapidly absorbed with a mean tmax of 1.47 ± 0.49 h and a mean elimination half-life of 4.0 ± 0.5 h. Phenylpropanolamine is predominantly excreted via the kidney with a mean renal clearance of 0.646 ± 0.089 liter/kg/h and 90.2 ± 1.7% excreted unchanged in the urine. The data were not well described using conventional one or two body compartment models. However, the incorporation of a discontinuous absorption phase into the models resulted in an improved overall fit with better characterisation of the absorption phase.
- Full Text:
- Date Issued: 1987
Outpatient compliance with theophylline and phenytoin therapy:
- Dowse, Roslind, Futter, William T
- Authors: Dowse, Roslind , Futter, William T
- Date: 1991
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157059 , vital:40083 , https://europepmc.org/article/med/1745939
- Description: Poor compliance with prescribed medication is a significant problem in chronic disease states and is often responsible for the apparent failure of therapy. The determinants and extent of non-compliance are commonly incorrectly perceived by doctors. During routine therapeutic drug monitoring of epileptic and asthmatic outpatients at a local day hospital, non-compliance was identified as a significant problem. A compliance study was conducted on 80 epileptic and asthmatic patients to determine the nature and extent of this problem. Non-compliance was measured using four different methods, which were then compared using chi 2 tests.
- Full Text:
- Date Issued: 1991
- Authors: Dowse, Roslind , Futter, William T
- Date: 1991
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157059 , vital:40083 , https://europepmc.org/article/med/1745939
- Description: Poor compliance with prescribed medication is a significant problem in chronic disease states and is often responsible for the apparent failure of therapy. The determinants and extent of non-compliance are commonly incorrectly perceived by doctors. During routine therapeutic drug monitoring of epileptic and asthmatic outpatients at a local day hospital, non-compliance was identified as a significant problem. A compliance study was conducted on 80 epileptic and asthmatic patients to determine the nature and extent of this problem. Non-compliance was measured using four different methods, which were then compared using chi 2 tests.
- Full Text:
- Date Issued: 1991
Phenylpropanolamine hydrochloride
- Kanfer, Isadore, Haigh, John M, Dowse, Roslind
- Authors: Kanfer, Isadore , Haigh, John M , Dowse, Roslind
- Date: 1983
- Language: English
- Type: Article
- Identifier: vital:6385 , http://hdl.handle.net/10962/d1006306
- Description: Phenylpropanolamine hydrochloride belongs to the sympathomimetic amine class of drugs and is structurally related to ephedrine hydrochloride. Its synthesis was first reported in 1910 and the first American patent was registered in 1939. The effects of phenylpropanolamine hydrochloride are largely the result of alpha-adrenergic agonist activity resulting from both direct stimulation of adrenergic receptors and release of neuronal norepinephrine. The principal adverse effect of phenylpropanolamine hydrochloride is dose-related hypertension and ventricular arrhythmia has been described. Phenylpropanolamine hydrochloride is widely used as a decongestant and it has been used as an anorectic agent for over 40 years. A report in 1939 described its effect as an hypertensive agent when administered parenterally.
- Full Text:
- Date Issued: 1983
- Authors: Kanfer, Isadore , Haigh, John M , Dowse, Roslind
- Date: 1983
- Language: English
- Type: Article
- Identifier: vital:6385 , http://hdl.handle.net/10962/d1006306
- Description: Phenylpropanolamine hydrochloride belongs to the sympathomimetic amine class of drugs and is structurally related to ephedrine hydrochloride. Its synthesis was first reported in 1910 and the first American patent was registered in 1939. The effects of phenylpropanolamine hydrochloride are largely the result of alpha-adrenergic agonist activity resulting from both direct stimulation of adrenergic receptors and release of neuronal norepinephrine. The principal adverse effect of phenylpropanolamine hydrochloride is dose-related hypertension and ventricular arrhythmia has been described. Phenylpropanolamine hydrochloride is widely used as a decongestant and it has been used as an anorectic agent for over 40 years. A report in 1939 described its effect as an hypertensive agent when administered parenterally.
- Full Text:
- Date Issued: 1983
In vitro-in vivo evaluation of a sustained release phenylpropanolamine oral dosage form
- Dowse, Roslind, Haigh, John M, Kanfer, Isadore
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1982
- Language: English
- Type: Article
- Identifier: vital:6360 , http://hdl.handle.net/10962/d1006052
- Description: There is increasing interest in measuring pharmacokinetic parameters of phenylpropanolamine (PPA), a sympathomimetic amine used in over-the-counter nasal decongestants and anorectic formulations. A high pressure liquid chromatographic (HPLC) procedure was developed to enable direct ultraviolet detection of PPA, after extraction from serum and urine, without prior derivatization of the drug. This method was used to assay samples obtained from a bioavailability study of BUBtained-releasePPA tablets. The mean serum and urine profiles obtained are presented. The sustained-release tablets were subjected to dissolution testing utilizing the United States Pharmacopoeia (USP XIX) rotating basket method. An internal standard was incorporated into the dissolution fluid to enable direct analysis of the samples by HPLC. A comparison of three different dissolution fluid regimens was carried out to determine if release of the drug was affected by the change in pH of the medium and to select the most convenient method for the final dissolution studies. Some preliminary observations relating to correlations between rate of drug release from the sustained-release dosage form and percent drug absorbed are presented.
- Full Text:
- Date Issued: 1982
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1982
- Language: English
- Type: Article
- Identifier: vital:6360 , http://hdl.handle.net/10962/d1006052
- Description: There is increasing interest in measuring pharmacokinetic parameters of phenylpropanolamine (PPA), a sympathomimetic amine used in over-the-counter nasal decongestants and anorectic formulations. A high pressure liquid chromatographic (HPLC) procedure was developed to enable direct ultraviolet detection of PPA, after extraction from serum and urine, without prior derivatization of the drug. This method was used to assay samples obtained from a bioavailability study of BUBtained-releasePPA tablets. The mean serum and urine profiles obtained are presented. The sustained-release tablets were subjected to dissolution testing utilizing the United States Pharmacopoeia (USP XIX) rotating basket method. An internal standard was incorporated into the dissolution fluid to enable direct analysis of the samples by HPLC. A comparison of three different dissolution fluid regimens was carried out to determine if release of the drug was affected by the change in pH of the medium and to select the most convenient method for the final dissolution studies. Some preliminary observations relating to correlations between rate of drug release from the sustained-release dosage form and percent drug absorbed are presented.
- Full Text:
- Date Issued: 1982
Determination of phenylpropanolamine in serum and urine by high performance liquid chromatography
- Dowse, Roslind, Haigh, John M, Kanfer, Isadore
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1983
- Language: English
- Type: Article
- Identifier: vital:6361 , http://hdl.handle.net/10962/d1006056
- Description: A high-performance liquid chromatographic analysis of phenylpropanolamine in human serum and urine without prior derivatization is presented. Using direct UV detection the method is sufficiently sensitive to detect 25 ng of drug/ml of serum or urine; the coefficients of variation at 25 ng/ml and 500 ng/ml were 5.16 and 2.12, respectively, in serum. The method involves serum and urine extraction at a basic pH with chloroform, a single back-extraction, and chromatography on a reverse-phase column. Serum and urine data following administration of a single 150-mg sustained-release tablet of phenylpropanolamine hydrochloride in 6 healthy volunteers demonstrates the suitability of the analytical method.
- Full Text:
- Date Issued: 1983
- Authors: Dowse, Roslind , Haigh, John M , Kanfer, Isadore
- Date: 1983
- Language: English
- Type: Article
- Identifier: vital:6361 , http://hdl.handle.net/10962/d1006056
- Description: A high-performance liquid chromatographic analysis of phenylpropanolamine in human serum and urine without prior derivatization is presented. Using direct UV detection the method is sufficiently sensitive to detect 25 ng of drug/ml of serum or urine; the coefficients of variation at 25 ng/ml and 500 ng/ml were 5.16 and 2.12, respectively, in serum. The method involves serum and urine extraction at a basic pH with chloroform, a single back-extraction, and chromatography on a reverse-phase column. Serum and urine data following administration of a single 150-mg sustained-release tablet of phenylpropanolamine hydrochloride in 6 healthy volunteers demonstrates the suitability of the analytical method.
- Full Text:
- Date Issued: 1983
Development and evaluation of pictograms on medication labels for patients with limited literacy skills in a culturally diverse multiethnic population:
- Kheir, Nadir, Awaisu, Ahmed, Radoui, Amina, El Badawi, Aya, Jean, Linda, Dowse, Roslind
- Authors: Kheir, Nadir , Awaisu, Ahmed , Radoui, Amina , El Badawi, Aya , Jean, Linda , Dowse, Roslind
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156720 , vital:40041 , https://doi.org/10.1016/j.sapharm.2013.11.003
- Description: Much of the migrant workforce in Qatar is of low literacy level and does not understand Arabic or English, presenting a significant challenge to health care professionals. Medicine labels are typically in Arabic and English and are therefore poorly understood by these migrant workers. To develop pictograms illustrating selected medicine label instructions and to evaluate comprehension of the pictograms or conventional text supported with verbal instructions in foreign workers with low literacy skills.
- Full Text:
- Date Issued: 2014
- Authors: Kheir, Nadir , Awaisu, Ahmed , Radoui, Amina , El Badawi, Aya , Jean, Linda , Dowse, Roslind
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156720 , vital:40041 , https://doi.org/10.1016/j.sapharm.2013.11.003
- Description: Much of the migrant workforce in Qatar is of low literacy level and does not understand Arabic or English, presenting a significant challenge to health care professionals. Medicine labels are typically in Arabic and English and are therefore poorly understood by these migrant workers. To develop pictograms illustrating selected medicine label instructions and to evaluate comprehension of the pictograms or conventional text supported with verbal instructions in foreign workers with low literacy skills.
- Full Text:
- Date Issued: 2014
Simple, illustrated medicines information improves ARV knowledge and patient self-efficacy in limited literacy South African HIV patients:
- Dowse, Roslind, Barford, Kirsty-Lee, Browne, Sara H
- Authors: Dowse, Roslind , Barford, Kirsty-Lee , Browne, Sara H
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156698 , vital:40039 , DOI: 10.1080/09540121.2014.931559
- Description: Few studies have investigated antiretroviral (ARV) knowledge and self-efficacy in limited literacy patients. Using a randomized controlled study design, we investigated the influence of a simple pre-tested patient information leaflet (PIL) containing both text and illustrations on HIV- and ARV-related knowledge and on self-efficacy over six months in a limited literacy African population. The recruited patients were randomly allocated to either control (standard care) or intervention group (standard care plus illustrated PIL). HIV and medicines-related knowledge was evaluated with a 22-question test at baseline, one, three, and six months. Self-efficacy was assessed using a modified version of the HIV Treatment Adherence Self-Efficacy Scale.
- Full Text:
- Date Issued: 2014
- Authors: Dowse, Roslind , Barford, Kirsty-Lee , Browne, Sara H
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156698 , vital:40039 , DOI: 10.1080/09540121.2014.931559
- Description: Few studies have investigated antiretroviral (ARV) knowledge and self-efficacy in limited literacy patients. Using a randomized controlled study design, we investigated the influence of a simple pre-tested patient information leaflet (PIL) containing both text and illustrations on HIV- and ARV-related knowledge and on self-efficacy over six months in a limited literacy African population. The recruited patients were randomly allocated to either control (standard care) or intervention group (standard care plus illustrated PIL). HIV and medicines-related knowledge was evaluated with a 22-question test at baseline, one, three, and six months. Self-efficacy was assessed using a modified version of the HIV Treatment Adherence Self-Efficacy Scale.
- Full Text:
- Date Issued: 2014
The limitations of current health literacy measures for use in developing countries:
- Authors: Dowse, Roslind
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156607 , vital:40030 , DOI: 10.1080/17538068.2016.1147742
- Description: Health literacy measures have largely emanated from developed countries, reflecting the characteristics of their economies, populations, and health systems. In contrast, it is disconcerting that health literacy appears to be so under-researched in developing countries (DCs), despite the likelihood of inadequate health literacy being endemic. In this commentary, I highlight some challenges when using existing health literacy measures in DCs and conclude with a summary of considerations when using/developing a tool for these populations.
- Full Text:
- Date Issued: 2016
- Authors: Dowse, Roslind
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156607 , vital:40030 , DOI: 10.1080/17538068.2016.1147742
- Description: Health literacy measures have largely emanated from developed countries, reflecting the characteristics of their economies, populations, and health systems. In contrast, it is disconcerting that health literacy appears to be so under-researched in developing countries (DCs), despite the likelihood of inadequate health literacy being endemic. In this commentary, I highlight some challenges when using existing health literacy measures in DCs and conclude with a summary of considerations when using/developing a tool for these populations.
- Full Text:
- Date Issued: 2016