Interacting drugs - summary

Asprin + Clopidrogrel

risk of life-threatening bleeding eg. intracranial and GI hemorrhage
 may be increased in high risk patients with TIA or ischemic stroke

Macrolide antibiotics eg, erythromycin + clopidrogrel
the antiplatelet effect of clopidogrel may be inhibited by certain
 macrolides and related antibiotics

NSAIDs +Clopidogrel
coadmin. of clopidogrel with naproxen was associated with increased
occult GI blood loss. Administer NSAIDs and clopidogrel with caution

Rifampicin + Clopidogrel
the antiplatelet effect of clopidogrel may be enhanced

Clopidogrel + Warfarin or Warfarin + Clopidogrel
the antiplatelet effect of clopidogrel may be enhanced
because of the increased risk of bleeding, undetake the coadmin
 of warfarin and clopidogrel with caution 

Clopidogrel + Bupropion
bupropion plasma concentration may be elevated increasing the
pharmacologic  and adverse reactions

Gastrointestinal upset,diarrhoea, and rash.

Serious events include bleeding and gastrointestinal haemorrhage.

Hypersensitivity.

Acute pathological bleeding such as peptic ulcer or intracranial hemorrhage.

Special preautions:

Pregnancy- No adequate studies of clopidigrel in pregnant women. Use with caution only if it required.

Lactation: Because of the potential side effects in the nursing infant, the physician must weigh the potential benefits against the benefits to the patient.

Date of Approval        02-09-08   

Indication-

Prophylaxis and thrombolic disorders

Dosage-

Adult- 75mg once daily with or without food.

Acute coronary syndrome- For ST-elevation myocardial infaction- in combination with aspirin- 75mg once daily .

Patients > 75 years old may be given a loading dose of 300mg.

Continue treatment for upto 28 days

For unstable angina, non-ST myocardial infaction initial - 300mg loading dose followed by 75mg once daily with aspirin 75 - 325mg once daily.

1.Tell patients that it may take them longer than usual to stop bleeding and they may bruise and /or bleed more easily when they take clopidrogel or clopidogrel combined with aspirin.

2.Patient should report any unusual bleeding to their health care provider

3. Instruct patients to inform their health care provider and dentist that they are taking clopidrogel and/or any other product known to bleeding before the surgery is scheduled and before a new drug is taken

Pharmacology:

Clopidogrel itself is inactive, but it is converted into an active metabolite. So the activity of clopidigrel is dependent on hepatic biotransformation. Platelets that adhere to damaged vessels walls are aggravated to secrete adenosine diphosphate(ADP) from the storage granules.

ADP causes platelets in the vicinity to swell and adhere to each other, further aggravating platelet aggregation. Clopidogrel blocks ADP receptor, leading to inhibition of fibronogen binding to the platelet receptor.

Pharmacokinetics:

Cipidogrel is rapidly absorbed on oral administration. It is inactive in vivo and undergoes hepatic activation. After oral clopidrogel administration , t max of the principal metabolite is approximately 1 hour.

Steady state level of the metabolite is acheived by about 8 hours of administration.The plasma elimination half-life of the active metabolite is 8 hours .

Food and antacids do not affect the bioavailability of clopidogrel.

Food and antacids do not affect the bioavailability of clopidogrel.

Take with or without food

Pregnancy-

No adequate studies of clopidigrel in pregnant women. Use with caution only if it required

 Lactation:

Because of the potential side effects in the nursing infant, the physician must weigh the potential benefits against the benefits to the patient.