An investigation into the feasibility of incorporating ketoconazole into solid lipid microparticles
- Authors: Jhundoo, Henusha Devi
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54701 , vital:26601
- Description: One of the major challenges of the oral administration of ketoconazole (KTZ), an inhibitor of sterol 14α demethylase, used in the management of systemic and topical mycoses in immuno-compromised and paediatric patients is the lack of availability of liquid dosage forms. In order to overcome this challenge, extemporaneous preparations have been manufactured by care-givers and health care providers by crushing or breaking solid oral dosage forms of KTZ and mixing with a vehicle to produce a liquid dosage form that can be swallowed by patients. However, the use of extemporaneous preparations may lead to under or over-dosing if the care-givers are not guided accordingly. Furthermore, the dearth of information on the stability of these KTZ-containing extemporaneous preparations may lead to ineffective antifungal therapy and complicate the problems of resistance as it is difficult to estimate the shelf-lives of these extemporaneous products under varying storage conditions due to the susceptibility of KTZ to chemical degradation. Therefore, there is a need for formulation scientists to develop novel drug delivery systems that avoid the need for extemporaneous preparations, possess well-established limits of stability and minimize the risks of systemic adverse effects to facilitate KTZ therapy. The use of solid lipid microparticles (SLM) as potential carriers for the oral administration of KTZ was investigated since solid lipid carriers are known to exhibit the advantages of traditional colloidal carriers. The research undertaken in these studies aimed to investigate the feasibility of developing and manufacturing solid lipid microparticles (SLM), using a simple micro-emulsion technique, as a carrier for KTZ. Prior to pre-formulation, formulation development and optimization studies of KTZ-loaded SLM, it was necessary to develop and validate an analytical method for the in vitro quantitation and characterization of KTZ in aqueous dispersions of SLM during development and assessment studies. An accurate, precise, specific and sensitive reversed-phase high performance liquid chromatographic (RP-HPLC) method coupled with UV detection at 206 nm was developed, optimized and validated for the analysis of KTZ in formulations. Formulation development studies were preceded by solubility studies of KTZ in different lipids. Labrafil® M2130 CS was found to exhibit the best solubilising potential for KTZ. Pre-formulation studies were also designed to determine the polymorphic behavior and the crystallinity of KTZ and Labrafil® M2130 CS that was used for subsequent manufacture of the solid lipid carriers. DSC and FTIR studies revealed that there were no changes in the crystallinity of KTZ or Labrafil® M2130 CS following exposure to a temperature of 60°C for 1 hour. In addition the potential for physicochemical interaction of KTZ with the lipid Labrafil® M2130 CS was investigated using DSC and FTIR and the results revealed that KTZ was molecularly dispersed in Labrafil® M2130 CS and that it is unlikely that KTZ would interact with the lipid. It was therefore established that KTZ and Labrafil® M2130 CS were thermo-stable at a temperature of 60°C and thus a micro-emulsion technique could be used to manufacture the KTZ-loaded SLM. Drug-free and KTZ-loaded SLM were prepared using a modified micro-emulsion technique that required the use of an Ultra-Turrax® homogenizer set at 24 000 rpm for 5 minutes followed by the use of the Erweka GmbH homogenizer. SLM were characterized in terms of particle size (PS), zeta potential (ZP), shape and surface morphology using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition drug loading capacity (DLC) and encapsulation efficiency (EE) of SLM for KTZ were assessed using RP-HPLC. Formulation development and optimization studies of KTZ-loaded SLM were initially aimed at selecting an emulsifying system that was able to stabilize the SLM in an aqueous dispersion. Successful formulations were selected based on their ability to remain physically stable on the day of manufacture. Pluronic® F68 used in combination with Lutrol® E40, Soluphor® P, Soluplus® produced unstable dispersions on the day of manufacture and these combinations were not investigated further. However, the formulation of a stable KTZ-loaded SLM dispersion was accomplished by use of a combination of Pluronic® F68, Tween 80 and sodium cholate as the surfactant system. Increasing amounts of Labrafil® M2130 CS resulted in the production of particles with low DLC and EE, a large PS and a relatively unchanged ZP. An optimum concentration of 10% w/v Labrafil® M2130 CS was selected to manufacture the KTZ-loaded SLM. Studies to determine the influence of KTZ loading on the quality of SLM revealed that concentrations of KTZ > 5% w/v led to a reduction in DLC and EE and an increase in PS with minimal impact on the ZP. Stability studies conducted at 25°C/65% RH and 40°C/75% RH for up to 30 days following manufacture revealed that batch SLM 15 manufactured using 10% w/v Labrafil® M2130 CS, 5% w/v KTZ and a combination of 4% w/v Pluronic® F-68, 2% w/v Tween 80 and 1% w/v sodium cholate produced the most stable dosage form when stored at 25°C/65% RH for up to 30 days. However, storage at 40°C/75% RH resulted in instability of the formulation. An aqueous dispersion of KTZ-loaded SLM has been developed and assessed and may offer an alternative to extemporaneous preparations used for KTZ therapy in paediatric and immuno-compromised patients.
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- Date Issued: 2015
Antibiotic stewardship: the role of clinical pharmacist
- Authors: Ramkhalawon, Shabeerah
- Date: 2015
- Subjects: Hospital pharmacies -- South Africa Pharmacists -- South Africa
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10948/10858 , vital:26830
- Description: South Africa has a high prevalence of infectious diseases; the major ones being the Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome epidemic, and tuberculosis. South Africa’s burden of resistant bacteria is also increasing. Antibiotic resistance in hospitalised patients leads to an increase in morbidity and mortality, resulting in longer hospital stays, and an increase in hospital costs. In order to counteract the problem of antibiotic resistance in hospitals and other healthcare facilities and preserve the efficacy of currently available antibiotics, there is a need for serious antibiotic management. Antibiotic stewardship initiatives have thus been put in place to guide healthcare professionals on the correct use of antibiotics. Clinical pharmacists can intervene and contribute to antibiotic stewardship owing to comprehensive knowledge of antibiotics, including the properties, uses, safety and efficacy of individual agents. There is a paucity of research to support the role of the clinical pharmacist in antibiotic stewardship in public sector hospitals. The current pharmacist staffing system within public sector hospitals does not adequately support pharmacists, in particular clinical pharmacists, to participate actively in antibiotic stewardship. The primary aim of the study was to evaluate the role of the clinical pharmacist in antibiotic stewardship in a public hospital setting. A secondary aim was to contribute towards more rational inpatient use of antibiotics in the general medical ward. The hypothesis for the study was that clinical pharmacists can make a positive contribution to the correct use of antibiotics in a public hospital setting. The study showed that the introduction of a pharmacist-driven antibiotic stewardship in the ward, using a prospective audit and feedback strategy, had a positive effect on overall appropriateness of antibiotic prescribing (Chi2=7.89; df=3; p=0.04815, Cramer’s V=0.13). However, this finding did not show any reduction in the volume of antibiotic use. Positive patient outcomes were achieved and shown through a reduction in the length of hospital stay (p=0.00487; one-way ANOVA). Although patients were not followed up on discharge to assess re-admission rates, the results are relevant in order to inform the hospital staff about the implementation of antibiotic stewardship at the public hospital setting with the aims of reducing inappropriate antibiotic prescribing and improving patient outcomes. From the results of the study, it can be concluded that the hypothesis was achieved and that the clinical pharmacist did play an integral role in antibiotic prescribing at the public hospital setting. Thus, it can be concluded that the study, though limited in its scope, achieved its aims and objectives, and showed that the clinical pharmacist does play an integral role in the rational use of antibiotics in a public hospital setting.
- Full Text:
- Date Issued: 2015
Development and manufacture of sustained release captopril beads
- Authors: Mhaka, Farai Arthur
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54712 , vital:26602
- Description: Hypertension has a high mortality rate in developing countries such as South Africa. Although the prevention and control of hypertension is a health priority, efforts to decrease the global burden of hypertension and improve control over the condition are inadequate. The use of angiotensin converting enzyme (ACE) inhibitors such as captopril (CPT) have been effective for the management of hypertension when used as first line therapy alone or in combination. Commercially available immediate release dosage forms containing 12.5, 25 and 50 mg of CPT are administered two or three times a day to treat hypertension. CPT degrades in aqueous media with the sulfhydryl functional moiety responsible for adverse effects such as hypersensitivity, taste disturbances and/or presenting with a dry hacking cough. CPT has a short elimination half-life of between 1.6 and 1.9 hours, which means that the compound is a suitable candidate for inclusion in sustained release (SR) dosage forms. Manufacturing a SR dosage form of coated beads for twice daily dosing may reduce the incidence and intensity of undesirable adverse effects, improve the stability of CPT and improve patient adherence. A stability indicating reversed-phase high performance liquid chromatographic (RP-HPLC) method was developed and optimised using a central composite design approach. As part of this approach the interactive effects of input factors, viz. pH, methanol (MeOH) content and column temperature on retention time, were investigated to achieve a separation with well-resolved and symmetrical peaks for CPT and salicylic acid. The method was validated using ICH guidelines and was found to be simple, linear, precise, accurate, selective and rapid for the in vitro quantitation of CPT. The method was successfully applied for the analysis of both commercially available and test formulations. Preformulation studies were undertaken to establish the physical and chemical properties of CPT, excipients and dosage forms to ensure the production of stabile and bioavailable products. Powder blends were assessed for flow properties using angle of repose (AOR), and bulk and tapped density, which were subsequently used to calculate Carr’s Index (CI) and the Hausner ratio (HR). The addition of talc resulted in the most powder blends with AOR, CI and HR that were within a range indicative of satisfactory to good flow properties. The use of talc was necessary to ensure that blending prior to wet granulation and extrusion-spheronisation would produce homogenous powders. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FT-IR) were used for the identification and purity of CPT alone and 1:1 binary mixtures with excipients in an effort to establish if CPT was likely to undergo physical and/or chemical modification during production. The DSC thermograms for all CPT-excipient mixtures revealed the presence of a melting endotherm that was wider, occurring at 110.93 °C (Tpeak for pure CPT). The characteristic peaks for specific functional groups were present in the FT-IR spectra for powder mixtures, indicating the absence of incompatibilities. Dialysis studies were used to investigate if the ammonium oleate present in Surelease® E-7-19010 interacted with CPT. The results suggests that an interaction between CPT and Surelease® E-7-19010 during processing of CPT beads was unlikely to occur. Preliminary investigations reveal that Methocel® K100M, Methocel® E4M, Avicel® PH102, Eudragit® RS PO, Surelease® E-7-19010 and talc are compatible with CPT and could be used for the manufacture of SR CPT beads. CPT beads were manufactured using extrusion-spheronisation and coated using a fluidised bed drier fitted with a Wurster insert. The amount of granulating fluid, coating levels, curing time and formulation composition were varied to achieve CPT release with specific criteria to develop a preliminary formulation. The coated beads met all desired quality attributes in respect of micromeritic and flow properties, content uniformity and friability. Response Surface Methodology was used to further optimise the SR CPT formulation. The Plackett-Burman design was used for this process to produce an SR dosage form with desirable quality attributes achieved by altering formulation composition, extrusion-spheronisation variables and coating parameters. ANOVA data revealed significant responses for yield, aspect ratio, sphericity, coating efficiency and cumulative percent CPT released at 2 and 12 hours. Formulations in which the high molecular weight HPMC were used in increased concentrations resulted in the formation of a sticky wet mass and extrudate, resulting in a decrease in yield. The application of a permeable, but insoluble Surelease® coat onto the surface of the beads formed a barrier that complements the activity of the hydrophilic matrix in preventing rapid dissolution and retarding the release of CPT from the beads. The amount of CPT released over 12 hours revealed that increasing the Methocel® K100M content entrapped CPT and retained it more efficiently in the hydrated matrix, resulting in a slow rate of CPT release. In vitro release data were fitted to a number of models in an attempt to elucidate mechanistic aspects of transport processes specific to CPT from the coated bead formulations. The results of fitting data from optimised batches revealed that the goodness of fit based on the adjusted correlation coefficient ranged between 0.953 and 0.976 for the Higuchi model, indicating that diffusion is a predominant factor that controls CPT release from the coated beads. The results of fitting data to the Korsmeyer-Peppas model suggest that the mechanism of CPT release includes transport of the dissolution medium from the vessel reservoir into the core of the bead due to osmotic potential, dissolution of CPT, mass transfer of the dissolved CPT within the core, partitioning between the solution and polymeric film, mass transfer of dissolved CPT through the film to ultimately reach the bulk dissolution fluid. A SR CPT bead formulation that has potential for further development and optimisation for scaled-up production using RSM approaches and Design of Experiments such as CCD or Box-Behnken has been successfully developed and manufactured using extrusion, spheronisation and coating processes. Assessment of all batches of beads manufactured exhibited satisfactory to good flow properties and demonstrated SR profiles over 12 hours that met USP criteria for SR dosage forms.
- Full Text:
- Date Issued: 2015
Formulation, development and assessment of tenofovir disoproxil fumarate-loaded pellets
- Authors: Dube, Tawanda
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54690 , vital:26600
- Description: Tenofovir disoproxil fumarate (TDF) is a novel nucleotide analog reverse transcriptase inhibitor that is recommended by the WHO for use in first line treatment of HIV infections. Due to the high dose of TDF for anti-retroviral treatment the formulation of a pellet dosage form may improve patient adherence by incorporation of a large dose in a relatively small dosage form. TDF is currently only available in tablet form. A simple, sensitive, selective, rapid, accurate, precise, stability indicating reversed-phase HPLC method was developed and validated in accordance with ICH guidelines and was successfully used for the analysis of TDF raw material and pharmaceutical dosage forms. Preformulation studies included an investigation of TDF-excipient and excipient-excipient interactions with all materials that could potentially be used to produce extruded and spheronized pellets. Nuclear Magnetic Resonance spectroscopy (NMR), Infrared Spectroscopy (IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric analysis were used for identification and purity testing of TDF and all excipients. DSC data revealed that no potential interactions between TDF and the excipients occurred suggesting that incompatibility reactions were unlikely during manufacture and storage. These findings were confirmed by IR analysis that revealed that no physical interaction was likely between any of the excipients used and TDF. DSC data also reveal the existence of the α and β-polymorphs of TDF as evidenced by two enthalpy changes observed on the resultant thermograms. The existence of two polymorphs is unlikely to result in incompatibility and was confirmed by IR analysis. The IR spectra reveal that all characteristic peaks for TDF were present in 1:1 binary mixtures. Therefore TDF is compatible with all excipients tested and thermal analysis confirmed the stability of TDF under manufacturing conditions. The temperature of degradation temperature established through DSC analysis confirmed that degradation during manufacture is unlikely as the temperature of manufacture is lower than that at which degradation occurs. Extrusion and spheronization were the processes used to manufacture TDF pellets as it is a simple and economic approach for production. The effects of extruder and spheronizer speed, amount of spheronization aid and diluents on the pellet size, shape, flow properties and TDF release characteristics were examined. In order to decrease the complexity of analysis and reduce the cost of development a Taguchi orthogonal array design of experiments was successfully applied to evaluate the impact of formulation variables on product characteristics and predict an optimized formulation with a minimum number of experiments. The use of Response Surface Methodology for the development and optimization of pharmaceutical systems, including the optimization of formulation composition, manufacturing processes and/or analytical methods is well established. However the application of RSM requires that accurate, precise and reproducible experimental conditions are used for the generation of reliable data and RSM use is limited due to sensitivity to experimental variability. The benefits of using RSM for formulation optimization include the fact that more than one variable can be investigated at a time and large amounts of information can be generated at the same time ensuring a more efficient process with respect to time and cost. An added advantage of this approach is that mathematical relationships can be generated for the models that are produced and provide formulation scientists with an indication of whether the effect(s) between factors are synergistic or antagonistic. There are several statistical design approaches that use RSM and a Taguchi orthogonal array design was selected for use in this optimization process as fewer experiments are required to generate data for the same number of factors to be investigated when compared to other statistical designs such as Central Composite (CCD) and Box-Behnken designs. The use of RSM clearly demonstrates the impact of different input variables on the % TDF released at 45 min and % TDF loaded into the particles. The amount of sorbitol and Kollidon® CL-M were the only significant variables that affected the % TDF released at 45 min and both excipients had an overall synergistic effect on the in vitro release of TDF. The prediction and manufacture of an optimized formulation led to the production of pellets that met predetermined specifications which was successfully achieved using RSM. The development of a TDF containing pellet dosage form has been achieved and the formulation, manufacture and characterization of the dosage form reveal that the product has the potential to be further developed.
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- Date Issued: 2015
The impact of a ward pharmacist in a surgical ward of a private hospital in the Eastern Cape
- Authors: Stone, Leanne Nicole , Burton, S F
- Date: 2015
- Subjects: Hospital pharmacies , Pharmaceutical services -- South Africa -- Eastern Cape , Pharmacists -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10948/5916 , vital:21012
- Description: Medication errors are becoming problematic in both hospital and outpatient settings worldwide. Inappropriate use of medication can cause harm to the patient and maintaining high levels of quality patient care is essential to protect all patients. Clinical pharmacy practice contributes to improved patient care by optimising medication therapy; and promoting health, wellness and disease prevention. The involvement of a pharmacist at a ward level has been shown to improve patient care; reduce mortality and morbidity rates; decrease healthcare costs; minimise medication errors; and improve outcomes of drug therapy. However, clinical pharmacy is a fairly new practice in South Africa and there are limited studies available. This study aimed to evaluate the perceived benefits of a ward-based pharmacist on the provision of pharmaceutical care to patients in a hospital setting and to consequently implement a ward-based pharmacy service. The objectives of the study were: (1) to assess, via a questionnaire, the perceptions and attitudes of medical practitioners and nurses to ward-based pharmacy prior to and after implementation of a ward-based pharmacy service, (2) to implement a ward-based pharmacy service in a selected hospital ward; (3) to document and analyse the nature of the work and activities that a ward pharmacist undertakes, and (4) to document and analyse the frequency and nature of ward pharmacist interventions. The study was conducted in a surgical ward of a private hospital in the Eastern Cape. The study design was an intervention study, using a mixed-methods design, with a convergent approach. A convenience sample of 106 patients was obtained over the eight week study period. Participation was voluntary and confidentiality was maintained at all times. Four data collection tools were used during the study and a pilot study was conducted to ensure their validity and reliability. The quantitative data was analysed statistically while the qualitative questions were analysed through coding the various responses. The results of the study showed that medical practitioners and nurses of a surgical ward had a positive attitude towards ward pharmacy both prior to and after the implementation of a ward pharmacy service. There were ward pharmacist interventions made in 50% (n=106) of the patients who participated in the study. A large percentage (57%; 50; n=87) of the ward pharmacist interventions were pharmacist-initiated interventions to optimise patient care while prescribing errors (51%; 19; n=37) were the most commonly occurring medication error. The majority of the medication items involved in the interventions (34%; 34; n=101) were related to the anti-microbial medication class. Overall, there was a 73% (36; n=49) acceptance rate of the ward pharmacist interventions that were made to both the medical practitioners and nurses. There were a number of factors that had a significant relationship with a ward pharmacist intervention being required which included: (1) number of medication items (p=0.001; Chi² test; p<0.0005 Student’s t-test), (2) length of hospital stay (p<0.0005; Chi² test), (3) presence of one or more chronic disease states (p=0.003; Chi² test) and (4) presence of one or more allergies (p=0.028; Chi² test). The ward pharmacist interventions were shown to be of clinical significance and to have a positive impact on the patients concerned. It can be concluded that the ward pharmacy service was beneficial to the patients, medical practitioners and nursing staff.
- Full Text:
- Date Issued: 2015
The quantification of fucoxanthin from selected South African marine brown algae (Phaeophyta) using HPLC-UV/Vis
- Authors: Mubaiwa, Byron Tawanda
- Date: 2015
- Subjects: Marine algae , Brown algae , High performance liquid chromatography , Functional foods , Xanthophylls , Carotenoids , Extraction (Chemistry)
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: vital:3868 , http://hdl.handle.net/10962/d1017879
- Description: Marine brown algae (seaweeds) are a rich source of fucoxanthin, a xanthophyll carotenoid that is naturally, an accessory pigment in the process of photosynthesis of sea vegetation such as Sargassum incisifolium. Fucoxanthin has been exploited by nutraceutical companies for its anti-obesity effects that has resulted in an increase of seaweed slimming preparations such as FucoThin™. The field is getting widespread consumer attention as interest in fucoxanthin has also transcended to its widespread biological potential which include cytotoxicity, anti-diabetic, anti-oxidant, anti-inflammatory and anti-plasmodium effects. We therefore wanted to identify a reliable source(s) of fucoxanthin from diverse samples of South African marine brown algae in order to explore our medicinal chemistry interests around the cytotoxicity and anti-malarial potential of fucoxanthin. A known source, Sargassum incisifolium, was used to isolate (maceration in CH₂Cl₂/MeOH at 35 °C followed by a hexane/EtOAc step gradient silica column of the crude extract and reversed phase semi-prep HPLC) and characterize (1D and 2D NMR) fucoxanthin (reference standard) in order to develop an analytical method for its determination in selected diverse brown algae commonly found in South Africa. The HPLC [Column: Phenomenex® Synergi™ (250 x 3.0 mm i.d); Mobile phase: ACN/H2O (95:5)] method developed for this analysis was validated according the guidelines set by the International Conference on Harmonization (ICH). Fifteen species were then assessed for fucoxanthin content (μg/g of dried weight) using the developed method. Stability studies on fucoxanthin were also carried out to assess photo- and pH degradation of fucoxanthin. Zonaria subarticulata (KOS130226-18) from Kenton-On-Sea beach and Sargassum incisifolium (PA130427-1) from Port Alfred beach were found to be the highest producers of fucoxanthin with 0.50 mg/g and 0.45 mg/g dried weight respectively. Fucoxanthin was found to be both photo-labile and sensitive to both acidic and basic pH environments. However, the pigment was more photostable in pure as opposed to extract form and also showed to be more stable at pH 10.0. Our findings show that Z. subarticulata and S. incisifolium could be reliable sources of fucoxanthin and can be considered as the algae to use in optimized extraction procedures in further studies. Also, when working with fucoxanthin, it is important to protect it from light. Any consideration of taking fucoxanthin preparation orally (as a nutraceutical) should consider protecting the active from the harsh conditions of the gastrointestinal tract. Any upscale production of fucoxanthin from seaweed should consider variations such as geographical, seasonal, lifecycle stage, etc. of identified algae as these may be important factors in obtaining effective concentrations of fucoxanthin.
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- Date Issued: 2015
Validity and accuracy of self-reported drug allergies
- Authors: Grant, Elzaan
- Date: 2015
- Subjects: Drug allergy , Medical history taking
- Language: English
- Type: Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10948/3295 , vital:20421
- Description: Purpose: Pharmacists must ensure the safe and effective use of medication, but often have only the documented patient history to guide assessment of therapy. There is a lack of information on the incidence of claimed drug allergies or the validity of these self-reported drug allergies in the South African population. Mislabelling of patients as being allergic to medication often deprives them of important therapeutic drugs and alternative agents may be more dangerous, less effective and more costly (Hung et al., 1994). The aim of the research was therefore to determine the incidence of drug allergies in patients admitted to a private hospital and to assess the validity of these self-reported drug allergies. Methods: A descriptive, non-experimental study design was used. Data was collected using a concurrent, cross-sectional approach and collected from patients admitted to hospital using Medical Chart Reviews and researcher-led, questionnaire based interviews. During the seven month sampling period, 693 patients were identified with one or more self-reported drug allergies. A subset of 99 patients (14.2%) consented to a researcher-led interview. The allergies were assigned to one of three groups based on the history: (i) High probability: signs and symptoms typical of an immunological reaction. (ii) Low probability: signs and symptoms of the reaction were predictable reactions or side effects of the drug. (iii) Unknown status: no information concerning the reaction history was available. Results: A total of 953 allergies were identified in the 693 patients, with a ratio of drug allergy to patient of 1.4:1. The majority of claimed allergies were to penicillin (39.2%), opioid analgesics (17.6%), other antimicrobials, including co-trimoxazole (13.5%), NSAIDs (9.9%) and unspecified “sulphur” allergy (8.7%). Descriptions of the “allergic” reactions were only recorded on 8.9% (62, n=693) of the reviewed charts. Only 56.5% (35, n=62) of the symptoms recorded as “allergy” were indicative of the event being allergic or immunological in nature. In total, 1.3% (9, n=693) of the patients with a self-reported allergy received the allergen while in hospital. In three cases this was the result of a pharmacist overlooking the recorded allergy, and dispensing the allergen to the patient. A total of 118 allergies were identified in the 99 interviewed patients, with a ratio of drug allergy to patient of 1.2:1. Inaccurate allergy history was found in 9.1% (9, n=99) of the interviewed patients. Overall, the majority of self-reported drug allergies (67.8%) had a “high probability” of being a true drug allergy. Allergies that were assigned into the high probability group were: penicillin (74.1%), co-trimoxazole (91.7%), NSAID‟s (55.6%) and 75.0% of opioids. Conclusion: In summary, the validity of self-reported drug allergies need to be determined before excluding medication from a patient‟s treatment options. Detailed descriptions can assist in the evaluation of self-reported allergies which would be advantageous to both prescribers and patients. Pharmacists need to play a bigger role in ensuring accurate documentation of drug allergy history, with detailed descriptions, in order to ensure safe and effective drug use within the hospital environment.
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- Date Issued: 2015