The Effects of Pharmaceutical Care Model Development at Warfarin Clinic in 30-Bed Community Hospital

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Pikrom Asokbunyarat
Tipada Samseethong


Anticoagulant drug, Warfarin, had many indications in Thailand but it has limited pharmacodynamic and pharmacokinetic. Because of a narrow therapeutic index and different response in individual person, overdose could cause severe bleeding while underdose could cause ineffective in treatment. Thus, a proactive pharmaceutical care model may improve effectiveness and manage drug related problems. Material and method: A retrospective study was conducted in Luangphopern Hospital. Total 32 patients who treatment in warfarin clinic were divided into 2 groups; a preintervention group had 16 patients during 1 January-31 December 2017 and a postintervention group had 29 patients who received improved pharmaceutical care during 1 January-31 December 2019. Data was collected from electronic medical record and pharmaceutical care record in warfarin clinic, Then analyzed to mean percentage of time in therapeutic range (TTR) and the percentage number of patients who had TTR more than 60% by T-test and chi–Square, respectively. Results: The patients were recruited with 16 patients control group and 29 patients treatment group. There was no significant different in characteristics of gender, age, and indication. However, time to follow up INR was statistically significant difference (P<0.001). The results showed that mean percentage of TTR in intervention group were improved from 49.30 ± 26.32 to 66.49 ± 25.71 (P=0.039) and the percentage of patients with TTR more than 60% were from 35.70 to 68.97 (P=0.041). When compared to control group. The most drug related problems were inappropriate behavior by patient. Conclusion: The development proactive of pharmaceutical care model in 30 beds community hospital can improve the TTR within target via finding the problem, processing the problem management and follow up for resolving. This model increases the efficiency and safety of warfarin treatment.


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Pharmaceutical Practice


Björkman IK, Sanner MA, Bernsten CB. Comparing 4 classification systems for drug-related problems: processes and functions. Res Social Adm Pharm 2008 Dec; 4(4): 320-331

Boonbaichaiyapruck S, Panchavinnin P, Suthichaiyakul T, et al. Behavior of prothrombin time (INR) in response to warfarin therapy in a Thai population. Thai Heart J 2006; 19(3): 85–89

Boonyapipat T, Wattanasombat S; Service plan committee in cardiology. Operation handbook of service plan in cardiology, Warfarin Clinic Management. Bangkok: O VIT (THAILAND); 2016

Chalongsuk R. Sample size. Thai J Pharm. 2007; 4: 1-15

Connolly SJ, Pogue J, Eikelboom J, et al. Benefit of oral anticoagulant over antiplatelet therapy in atrial fibrillation depends on the quality of international normalized ratio control achieved by centers and countries as measured by time in therapeutic range. Circulation. 2008 Nov 11; 118(20): 2029-2037

Deoisares R, Rojnuckarin P. Prevalence of VKORC1 Single Nucleotide Polymorphism (SNP) – 1639 in Thai Adult Patients Who Have INR More Than 4 from Warfarin. J Hematol Transfus Med 2010; 20: 113-118

Gómez-Outes A, Terleira-Fernández AI, Calvo-Rojas G, et al. Direct oral anticoagulants for stroke prevention in patients with atrial fibrillation: meta-analysis by geographic region with a focus on European patients. Br J Clin Pharmacol 2016; 82(3): 633-644

Hanrinth R. Classification for drug related problems. Thai J Pharm Prac 2009; 1(1): 84-96

Hart RG, Pearce LA, Aguilar MI. Meta-analysis: antithrombotic therapy to prevent stroke in patients who have nonvalvular atrial fibrillation. Ann Intern Med 2007; 146: 857–867.

Hongthong C, Dudsadeeprasert J, Kessomboon N. IHoMe-PCC: Pharmaceutical Care from a Systems Perspective in Case Study of Schizophrenia Patients. IJPS 2019; 15(3): 84-94

Jaidee S, Kulsombon V, Sriviriyanupap W; National Health Security office, Health Consumer Protection Program, Primary care pharmacist club. Handbook for pharmacist in primary care unit operation. 1st ed: Bangkok: Sri Mueang Printing; 2017

Jarernsiripornkul N, Polkote N. Retrospective study of adverse reaction from warfarin at Srinagarind Hospital, Khon Kaen Province. KKU Res J 2006; 11: 228-236

Jittsue A, Yeephu S, Potaros T, et al. Study of Knowledge and Drug Related Problems of Warfarin at Outpatient Vachiraphuket Hospital. Songkla Med J 2015; 33(2): 83-92

Lampert ML, Kraehenbuehl S, Hug BL. Drug-related problems: evaluation of a classification system in the daily practice of a Swiss University Hospital. Pharm World Sci 2008; 30: 768-76.

Lee S, Hwang HJ, Kim JM, Chung CS, Kim JH. CYP2C19 polymorphism in Korean patients on warfarin therapy. Arch Pharm Res 2007; 30: 344-349

Marcatto LR, Sacilotto L, Tavares LC, et al. Pharmaceutical Care Increases Time in Therapeutic Range of Patients With Poor Quality of Anticoagulation With Warfarin. Front Pharmacol. 2018 Sep 21;9:1052.

McAlister FA, Wiebe N, Hemmelgarn BR. Time in therapeutic range and stability over time for warfarin users in clinical practice: a retrospective cohort study using linked routinely collected health data in Alberta, Canada. BMJ Open 2018 Jan 29; 8(1): e016980

National Statistical Office of Thailand. Health statistics [Internet]. Bangkok [cited 2021 Jan 24]. Available from:

Pharmaceutical Care Network Europe Foundation. PCNE classification for drug related problems V 8.02 [online]. 2020.[cited Oct 31, 2020]. Available from:

Priksri W, Rattanavipanon W, Saejear W, et al. Incidence, risk factors, and outcomes of warfarin-associated major bleeding in Thai population. Pharmacoepidemiol Drug Saf 2019; 28(7): 942-950.

Sangviroon A, Panomvana D, Tassaneeyakul W, et al. Pharmacokinetic and pharmacodynamic variation associated with VKORC1 and CYP2C9 polymorphisms in Thai patients taking warfarin. Drug Metab Pharmacokinet 2010; 25(6): 531-538

Saokaew S, Sapoo U, Nathisuwan S, et al. Anticoagulation control of pharmacist-managed collaborative care versus usual care in Thailand. Int J Clin Pharm 2012; 34(1): 105-112

Sermsathanasawadi N, Sritongsathian C, Pongrattanaman N, et al. The Influence of VKORC1 Polymorphisms on Warfarin Doses in Thai Patients with Deep Vein Thrombosis. J Med Assoc Thai 2015; 98: 549

Silaruks S, Kanjanavanit R, Phrommintiku A, et al. Guidelines for the management of patients on oral anticoagulants. Bangkok:The Heart Association of Thailand under the Royal Patronage of H.M. the King; 2011.

Sukasem C, Tunthong R, Chamnanphon M, et al. CYP2C19 polymorphisms in the Thai population and the clinical response to clopidogrel in patients with atherothrombotic-risk factors. Pharmgenomics Pers Med 2013; 6: 85-91

Tantipiwattanaskul K. The Influence of Patient Factors on Medication Adherence in Ambulatory Care Unit at Bangplama Hospital, Suphanburi. JHS 2019;28 Suppl 1: S107-119

Tantiviyavanit J, Chaiyasu R. Effects of Pharmaceutical Care on Patients taking Warfarin at Pattani Hospital. TJPP 2013 Jul-Dec; 5(2): 108 -119

Tassaneeyakul W, Mahatthanatrakul W, Niwatananun K, et al. CYP2C19 Genetic Polymorphism in Thai, Burmese and Karen Populations. Drug Metab Pharmacokinet. 2006 Aug; 21(4): 286-290

Wangnirattisai N, Supakul S, Arunmanakul P. Effects of Pharmaceutical Care in Patients Receiving Warfarin from the Warfarin Clinic at Sawanpracharak Hospital. Thai J Pharm Pract 2018; 10(1): 120-128

Wattanachai N, Kaewmoongkun S, Makarawate P, et al., The Study of CYP2C19 Genetic Polymorphisms in Thai Patients Taking Stable Doses of Warfarin. Thai J Pharmacol 2018; 40: 5-16

Wattanachai N, Kaewmoongkun S. Warfarin: Pharmacology and Factors Affecting its Response. Srinagarind Med J 2017; 32(2): 189-199

Zhang H, Ma K, Liu W, et al. Impact of CYP2C19 gene polymorphism on warfarin maintenance doses in patients with non-valvular atrial fibrillation. Gene 2016; 591: 80-84