Clopidogrel (Plavix®)Carmen G. Rolf

Lamar UniversityFall 2015

Clopidogrel Antiplatelet Inhibits ADP Prevents

Aggregation Activation

Metabolized in liver Quick acting No antidote Risk: bleeding

Acute Coronary Syndromes First line of defense

after previous MI Treats stable and

unstable angina Helps prevent new MI Can be combined with

aspirin Use with stents

http://humanbodydisease.com/ischemic-heart-disease-intro-795.html

Intended Drug Response Irreversibly binds to

P2Y12 receptors on platelet surfaces

Prevents ADP from binding to receptors

Platelet inactive for life-span (7-10 days)

Prevents clot formationThienopyridines block ADP receptors. Source:Harvey, R; Champe, P “Lippincott illustrated reviews: Pharmacology”, 4th edition. LWW: 2009.

Potential Interactions Hundreds of drugs Proton Pump Inhibitors

Prilosec®, Nexium®, pantoprazole (Protonix®) Warfarin (Coumadin®) NSAIDs SSRIs

Prozac® SNRIs

Adverse Reactions

Bleeding is greatest risk

Increased risk when combined with aspirin

Side Effects/Patient reports Headache GI upset Myalgias Skin problems Confusion

Pharmacokinetics Easily absorbed from

intestine 50% available 6 hr half-life Metabolized in liver

2 step process 85% inactive Uses P450 enzymes

CYP2C19

Results in 2 hours Steady state within 1 week 40 – 60 % platelet

inhibition in normal metabolizers

Ultra rapid to poor metabolizers

Stop at least 5 days before invasive procedures

Drug Binding Issues Any drugs that use the CYP2C19 enzyme for

metabolism Most important: Proton pump inhibitors

Increased risk of clots Omeprazole and esomeprazole worst Pantoprazole better

Improving Communication All insurance companies

involved in oversight with pharmacists

Educate insurance companies on the benefit to risk ratio of clopidogrel versus warfarin

Encourage all providers to communicate with each other

Refine electronic medical records to either alert or allow all providers access to medication changes

Encourage patients to report all medications and side effects to all providers

Home Health Care Report new medications

found in home to all providers

Educate patient Need for med Possible side effects Update/report med list

Educate insurance companies

References Allerman, A.A. & Goldfarb, E.B. (2013). Anticoagulation disturbances. In V.P. Arcangelo & A.M.

Peterson (Eds.). Pharmacotherapeutics for advanced practice (3rd ed.) (pp. 764-803). Philadelphia, PA: Lippincott, Williams, & Wilkins.

Brashers, V.L. (2014). Alterations in cardiovascular function. In McCance, K.L., Huether, S.E., Brashers, V.L., & Rote, N.S. (Eds.). Pathophysiology: the biologic basis for disease in adults and children (7th ed.), pp. 1129-1193. St. Louis, MO: Elsevier.

Reese, A.M. & Peterson, A.M. (2013). Chronic stable angina. In V.P. Arcangelo & A.M. Peterson (Eds.). Pharmacotherapeutics for advanced practice. (3rd ed.) (pp. 263-277). Philadelphia, PA: Lippincott, Williams, & Wilkins.

Rote, N.S., & McNance, K.L. (2014). Structure and function of the hematologic system. In McCance, K.L., Huether, S.E., Brashers, V.L., & Rote, N.S. (Eds.). Pathophysiology: the biologic basis for disease in adults and children (7th ed.), pp. 945-981. St. Louis, MO: Elsevier.

The Rx List. (2015). Plavix (clopidogrel bisulfate) tablets. Retrieved from, http://www.rxlist.com/plavix-drug.htm

Wang, Z.Y., Chen, M., Zhu, L.L., Zeng, S., Xiang, M.X., & Zhou, Q. (2015). Pharmacokinetic drug interactions with clopidogrel: updated review and risk management in combination therapy. Theraputics and Clinical Risk Management, 11, pp.449-467. Doi: http://dx.doi.org/10.2147/TCRM.S80437