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Displaying publications 41 - 53 of 53 in total

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Michaelis-Menten pharmacokinetics of phenytoin in adult Malaysian patients

Ismail R, Rahman AF

J Clin Pharm Ther, 1990 Dec;15(6):411-7.
PMID: 2089048

We reviewed our data from 122 records of patients taking phenytoin for the treatment of various types of epilepsy and selected 15 (age range 10-43 years old) who were on phenytoin alone to calculate Michaelis-Menten pharmacokinetic parameters. The average Vm and Km for this age group was found to be 8.45 mg/kg/day and 6.72 mg/litre, respectively. Km was independent of age and weight. Vm correlated well with weight but there was no relationship with age.
Heterogeneity of the CYP2D6 gene among Malays in Malaysia

Teh LK, Ismail R, Yusoff R, Hussein A, Isa MN, Rahman AR

J Clin Pharm Ther, 2001 Jun;26(3):205-11.
PMID: 11422605

Although Malays shared an origin with Chinese, their evolution saw substantial divergences. Phenotyping studies suggested that they differed in CYP2D6 polymorphism, with higher PM prevalence but lesser right-shift for debrisoquine MRs.
An observational study of drug administration errors in a Malaysian hospital (study of drug administration errors)

Chua SS, Tea MH, Rahman MH

J Clin Pharm Ther, 2009 Apr;34(2):215-23.
PMID: 19250142 DOI: 10.1111/j.1365-2710.2008.00997.x

Drug administration errors were the second most frequent type of medication errors, after prescribing errors but the latter were often intercepted hence, administration errors were more probably to reach the patients. Therefore, this study was conducted to determine the frequency and types of drug administration errors in a Malaysian hospital ward.
Clinical relevance of VKORC1 (G-1639A and C1173T) and CYP2C9*3 among patients on warfarin

Teh LK, Langmia IM, Fazleen Haslinda MH, Ngow HA, Roziah MJ, Harun R, et al.

J Clin Pharm Ther, 2012 Apr;37(2):232-6.
PMID: 21507031 DOI: 10.1111/j.1365-2710.2011.01262.x

Testing for cytochrome P450-2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) variant alleles is recommended by the FDA for dosing of warfarin. However, dose prediction models derived from data obtained in one population may not be applicable to another. We therefore studied the impact of genetic polymorphisms of CYP2C9 and VKORC1 on warfarin dose requirement in Malaysia.
Polymorphism of ITPA 94C>A and risk of adverse effects among patients with acute lymphoblastic leukaemia treated with 6-mercaptopurine

Wan Rosalina WR, Teh LK, Mohamad N, Nasir A, Yusoff R, Baba AA, et al.

J Clin Pharm Ther, 2012 Apr;37(2):237-41.
PMID: 21545474 DOI: 10.1111/j.1365-2710.2011.01272.x

Genetic polymorphisms of thiopurine S-methyltransferase (TPMT) and inosine triphosphate pyrophosphohydrolase (ITPA 94C>A) contribute to variable responses, including fatal adverse effects, among subjects treated with 6-mercaptopurine (6-MP). Our objectives were to investigate the distribution of specific TPMT and ITPA genotypes in healthy subjects and patients with acute lymphoblastic leukaemia (ALL) from the three main ethnic groups (Malays, Chinese and Indians) in Malaysia and the association of the polymorphisms with adverse effects of 6-MP.
Mutational analysis of CYP2C8 in hypertensive patients using denaturing high performance liquid chromatography

Teh LK, Zahri MK, Zakaria ZA, Ismail R, Salleh MZ

J Clin Pharm Ther, 2010 Dec;35(6):723-8.
PMID: 21054465 DOI: 10.1111/j.1365-2710.2009.01146.x

CYP2C8 is involved in the cytochrome P450 (CYP) epoxygenase pathway. Arachidonic acid metabolites such as epoxyeicosatrienenoic acids and hydroxyeicosatetrenoic acids, produced may have a role in hypertension. We aimed to develop a medium through-put method for screening samples of known and new mutations of CYP2C8 using denaturing high performance liquid chromatography (DHPLC).
A survey of patient-orientated services in community pharmacy practice in Malaysia

Sarriff A

J Clin Pharm Ther, 1994 Feb;19(1):57-60.
PMID: 8188792

This survey explored patient-orientated services, beyond processing of prescriptions and dispensing of medications, provided by the Malaysian community pharmacist. The results revealed a trend towards the provision of such activities. Although this was not widely implemented by the pharmacists, activities such as patient counselling and providing drug information were part of their daily practice. Lack of time, large workload, and inadequate drug information sources were the constraints cited by the pharmacists for the provision of such activities. If willingness and abilities to perform such activities were the significant barriers, then educational programmes should be initiated to provide the missing competencies.
Using pictograms to assist caregivers in liquid medication administration: a systematic review

Chan HK, Hassali MA, Lim CJ, Saleem F, Tan WL

J Clin Pharm Ther, 2015 Jun;40(3):266-72.
PMID: 25865563 DOI: 10.1111/jcpt.12272

WHAT IS KNOWN AND OBJECTIVE: It has been reported that more than 80% of out-of-hospital medication errors among the young children involve liquid formulations. The usefulness of pictorial aids to improve communication of medication instructions has not been extensively investigated for child health. The objective of this study was to determine the effectiveness of pictorial aids used to assist caregivers in the administration of liquid medications.
METHODS: MEDLINE, CINAHL, PsycINFO, ScienceDirect, Scopus and the Cochrane Library were searched for articles published up to February 2015. Studies that used pictorial aids with liquid medications and measured at least one of the following outcomes were included: dosing accuracy, comprehension of medication instructions, recall of information and adherence of caregivers. Two authors independently selected studies, extracted data and assessed methodological quality of studies using the Cochrane Collaboration's tool.
RESULTS AND DISCUSSION: Five experimental studies (four hospital based and one community based) with a total of 962 participants were included. A wide range of liquid formulations were studied, including both prescription and over-the-counter medications. The existing findings suggest that pictographic interventions reduced dosing errors, enhanced comprehension and recall of medication instructions and improved adherence of caregivers. Incorporating pictorial aids into verbal medication counselling or text-based instructions was more beneficial than using the single approach alone. Mixed results were identified for the relationship between health literacy of caregivers and effectiveness of pictorial aids.
WHAT IS NEW AND CONCLUSION: The evidence remains limited due to the small number of studies found and variations in methodological quality. This review suggests that pictorial aids might be potential interventions, but more high-quality studies are needed to support the routine use of any pictogram-based materials with liquid medications in the clinical settings.
KEYWORDS: caregivers; graphics; health literacy; medication adherence; medication errors; paediatrics
The relevance of CYP2D6 genetic polymorphism on chronic metoprolol therapy in cardiovascular patients

Ismail R, Teh LK

J Clin Pharm Ther, 2006 Feb;31(1):99-109.
PMID: 16476126

CYP2D6 polymorphisms are well described in normal populations but there are few data on its clinical significance. We therefore investigated the influence of CYP2D6 polymorphism on steady-state plasma concentrations and apparent oral clearance of metoprolol in patients with cardiovascular diseases.
A systematic review of the efficacy and tolerability of hydroxyethylrutosides for improvement of the signs and symptoms of chronic venous insufficiency

Aziz Z, Tang WL, Chong NJ, Tho LY

J Clin Pharm Ther, 2015 Apr;40(2):177-85.
PMID: 25630350 DOI: 10.1111/jcpt.12247

Rutoside (rutin; quercetin rutinoside) is a glycoside found in various plant products, including apples, citrus fruits and cranberries. Hydroxyethylrutosides (HR) are semisynthetic derivatives sold as standardized products for the treatment of chronic venous insufficiency (CVI). Commercially available products include Relvène(®) (France), Venoruton(®) (Switzerland) and Paroven(®) (United Kingdom). However, the evidence for their efficacy is inconclusive. The aim of this systematic review was to evaluate the evidence of efficacy and tolerability of hydroxyethylrutosides for CVI.
Development of a hyponatremia screening tool (ABCDF-S score) for patients with hypertension using thiazide diuretic agents

Kanchanasurakit S, Saokaew S, Siriplabpla W, Arsu A, Boonmak W, Watcharasiriphong W

J Clin Pharm Ther, 2020 Oct;45(5):997-1005.
PMID: 32012317 DOI: 10.1111/jcpt.13123

WHAT IS KNOWN AND OBJECTIVE: Hyponatremia is a common side effect of thiazide diuretics that can lead to increased mortality and hospitalization. A rapid and accurate screening tool is needed for rapid and appropriate management. In this study, we report on the development of a simple clinical screening tool for hyponatremia using thiazide diuretics.
METHODS: This nested case-control study was performed by collecting data from 1 January 2015 to 30 June 2017. Univariable and multivariable logistic regressions were used to identify potential risk factors. The regression coefficients were converted into item scores by dividing each regression coefficient with the minimum coefficient in the model and rounding to the nearest integer. This value was then summed to the total score. The prediction power of the model was determined by the area under the receiver operating characteristic curve (AuROC).
RESULTS AND DISCUSSION: Six clinical risk factors, namely age ≥65 years, benzodiazepine use, history of a cerebrovascular accident, dose of hydrochlorothiazide ≥25 mg, female sex and statin use, were included in our ABCDF-S score. The model showed good power of prediction (AuROC 81.53%, 95% confidence interval [CI]: 78%-84%) and good calibration (Hosmer-Lemeshow X2 = 23.20; P = .39). The positive likelihood ratios of hyponatremia in patients with low risk (score ≤ 6) and high risk (score ≥ 8) were 0.26 (95% CI: 0.21-0.32) and 3.89 (95% CI: 3.11-4.86), respectively.
WHAT IS NEW AND CONCLUSION: The screening tool with six risk predictors provided a useful prediction index for thiazide-associated hyponatremia. However, further validation of the tool is warranted prior to its utilization in routine clinical practice.
An analysis of genetic association in opioid dependence susceptibility

Nagaya D, Zahari Z, Saleem M, Yahaya BH, Tan SC, Yusoff NM

J Clin Pharm Ther, 2018 Feb;43(1):80-86.
PMID: 28656735 DOI: 10.1111/jcpt.12585

WHAT IS KNOWN: Drug addiction is a novelty-seeking personality trait that is associated with the candidate genes OPRD1 (opioid delta receptors), OPRK1 (opioid kappa receptors) and PDYN (prodynorphin). However, associations between single nucleotide polymorphisms (SNPs) rs1042114 (80G>T) of the OPRD1 gene, rs702764 (843 A>G) of the OPRK1 gene, and rs910080 (3' UTR _743T>C), rs1997794 (5' UTR -381A>G) and rs1022563 (3' UTR) of the PDYN gene and novelty seeking remain controversial as reported results have not been reproducible.
OBJECTIVE: The goal of this study was to determine the frequencies of SNPs rs1042114, rs702764, rs1997794, rs1022563 and rs910080 in the Malaysian population and to study their association with opioid dependence in Malaysian Malays.
METHODS: A total of 459 Malay male with opioid dependence and 543 healthy male (controls) subjects were included in this study. SNPs were genotyped using the TaqMan SNP genotyping assay. Statistical analysis was performed using Golden Helix SVS software suite to identify the distribution of allele and genotype frequencies, and SNP-SNP interactions were also analysed in this study.
RESULTS AND DISCUSSION: SNP rs1042114 in the OPRD1 gene is strongly associated with opiate addiction (P=.0001). In individuals homozygous for this risk allele, the likelihood of opiate addiction is increased by a factor 1.62 (95% confidence interval (CI) 1.412-1.875). Polymorphic alleles at SNP rs702764 of OPRK1 were not associated with opioid dependence. A significant association between opioid dependence and SNP rs910080 of PDYN (P=.0217) was detected, but there was no association for SNPs rs199774 and rs1022563. A significant interaction was also identified between homozygous wild-type genotype TT of rs702764 with the risk genotypes TG/GG of rs1042114 (odds ratio (OR)=2.111 (95% CI 1.227-3.631), P=.0069) and with the risk genotypes GA/AA of rs910080 (OR=1.415 (95% CI 1.04-1.912), P=.0239).
WHAT IS NEW AND CONCLUSION: The results indicate that SNPs rs1042114 and rs910080 contribute to vulnerability to opioid dependence in the Malaysian Malay population. These results will help us to understand the effect of the SNPs and the SNP-SNP interaction on opioid dependence and may assist in efforts to screen vulnerable individuals and match them with individually tailored prevention and treatment strategies.
Clinically important drug-drug interactions in primary care

Dhabali AA, Awang R, Zyoud SH

J Clin Pharm Ther, 2012 Aug;37(4):426-30.
PMID: 22081958 DOI: 10.1111/j.1365-2710.2011.01314.x

WHAT IS KNOWN AND OBJECTIVE: Drug-drug interactions (DDIs) cause considerable morbidity and mortality worldwide and may lead to hospital admission. Sophisticated computerized drug information and monitoring systems, more recently established in many of the emerging economies, including Malaysia, are capturing useful information on prescribing. Our aim is to report on an investigation of potentially serious DDIs, using a university primary care-based system capturing prescription records from its primary care services.
METHODS: We retrospectively collected data from two academic years over 20 months from computerized databases at the Universiti Sains Malaysia (USM) from users of the USM primary care services.
RESULTS AND DISCUSSION: Three hundred and eighty-six DDI events were observed in a cohort of 208 exposed patients from a total of 23,733 patients, representing a 2-year period prevalence of 876·4 per 100,000 patients. Of the 208 exposed patients, 138 (66·3%) were exposed to one DDI event, 29 (13·9%) to two DDI events, 15 (7·2%) to three DDI events, 6 (2·9%) to four DDI events and 20 (9·6%) to more than five DDI events. Overall, an increasing mean number of episodes of DDIs was noted among exposed patients within the age category ≥70 years (P=0·01), an increasing trend in the number of medications prescribed (P<0·001) and an increasing trend in the number of long-term therapeutic groups (P<0·001).
WHAT IS NEW AND CONCLUSION: We describe the prevalence of clinically important DDIs in an emerging economy setting and identify the more common potentially serious DDIs. In line with the observations in developed economies, a higher number of episodes of DDIs were seen in patients aged ≥70 years and with more medications prescribed. The easiest method to reduce the frequency of DDIs is to reduce the number of medications prescribed. Therapeutic alternatives should be selected cautiously.

Study site: e Universiti Sains Malaysia (USM