Is clopidogrel a CYP2C19 inhibitor?

Clopidogrel is an inactive prodrug that requires hepatic bioactivation via several cytochrome P450 enzymes, including CYP2C19. The active metabolite irreversibly inhibits the platelet ADP receptor, P2Y12.

What does CYP2C19 do to clopidogrel?

Clopidogrel is a prodrug, and CYP2C19 is the major enzyme involved in the conversion of clopidogrel into an active metabolite.

What drugs inhibit CYP2C19?

Cytochrome P-450 CYP2C19 Inhibitors

How do CYP2C19 inhibitors affect the metabolism of clopidogrel?

In particular, carriers of loss-of-function CYP2C19 alleles have impaired metabolism of clopidogrel, which results in decreased inhibition of platelet aggregation and increased cardiovascular risk.

Can I take omeprazole with clopidogrel?

Concomitant use of clopidogrel and omeprazole or esomeprazole is to be discouraged unless considered essential. Doctors should check whether patients who are taking clopidogrel are also buying over-the-counter omeprazole and consider whether other gastrointestinal therapies would be more suitable.

What is the antidote for clopidogrel?

The only way to overcome the antiplatelet effect of clopidogrel is with platelet transfusions because clopidogrel irreversibly inhibits platelet function for the life of the platelet, and there is no known antidote.

How do you know if clopidogrel is working?

Talk to a pharmacist or your doctor before buying any over-the-counter medicine to check if it is compatible with clopidogrel. You may notice that you bruise or bleed more easily and it will take longer to stop bleeding while you are taking clopidogrel. This shows that clopidogrel is working.

What happens if CYP2C19 is inhibited?

CYP2C19 Inhibitors Drugs that inhibit CYP2C19 activity (Table 2) are likely to increase the plasma concentrations of the medications listed with an asterisk in Table 1, and in some cases adverse outcomes may occur.

Why do some patients not respond to clopidogrel?

Some people with clopidogrel resistance have a reduced ability to convert the drug to its active form because of a polymorphism in one copy of the CYP2C19 gene that results in decreased enzyme activity. These individuals are described as intermediate metabolizers.

How is clopidogrel used to diagnose CYP2C19?

The warning states that tests are available to identify patients who are CYP2C19 poor metabolizers, and to consider the use of another platelet P2Y12 inhibitor in patients identified as CYP2C19 poor metabolizers. The effectiveness of clopidogrel is also reduced in individuals who are CYP2C19 intermediate metabolizers.

Are there any drugs that work on CYP2C19?

CYP2C19. CYP2C19 is a liver enzyme that acts on at least 10% of drugs in current clinical use, most notably the antiplatelet treatment clopidogrel (Plavix) also drugs that treat pain associated with ulcers, such as omeprazole, antiseizure drugs such as mephenytoin, the antimalarial proguanil, and the anxiolytic diazepam.

When did the FDA change the label for clopidogrel?

March 2017: The FDA-approved label for clopidogrel (Plavix) was recently updated (September 2016) and warns that patients who are CYP2C19 poor metabolizers may have diminished effectiveness of the drug as compared to patients with normal CYP2C19 function.

How does CYP2C19 affect the effectiveness of Plavix?

The alleles CYP2C19*2 and *3 may reduce the efficacy of clopidogrel (Plavix), an antiplatelet medication. The basis for this reduced effect of clopidogrel in patients who have a gene of reduced activity may seem somewhat paradoxical, but can be understood as follows.