ADMINISTRATION ROUTES:
PO, NG
ALTERNATIVE NAMES:
Plavix
ICU INDICATIONS:
- Treatment of acute coronary syndromes (especially post angioplasty when stents are deployed)
- Prophylaxis of vascular ischaemic events (mainly in patients with coronary stents)
PRESENTATION AND ADMINISTRATION:
PO:
Apo-clopidogrel 75mg tablets (reddish brown) Plavix 75mg tablets (pink)
DOSAGE:
PO/NG:
300 mg loading dose followed by 75mg once daily
Plavix brand clopidogrel can be crushed, mixed with water and administered via a nasogastric tube
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose as in normal renal function
DOSAGE IN PAEDIATRICS:
PO:
1.5 mg/kg daily
See PRECAUTIONS: Paediatric Use
CLINICAL PHARMACOLOGY:
Clopidogrel is a platelet aggregation inhibitor. It selectively inhibits the binding of adenosine diphosphate (ADP) to its platelet receptor and the subsequent ADP-mediated activation of the glycoprotein GPIIb/IIIa complex, thereby inhibiting platelet aggregation.
CONTRAINDICATIONS:
- Hypersensitivity to clopidogrel
- Active bleeding
WARNINGS:
Thrombotic Thrombocytopenic Purpura (TTP):
TTP has been reported rarely following use of clopidogrel bisulfate, sometimes after a short exposure (<2 weeks). TTP is a serious condition that can be fatal and requires urgent treatment including plasmapheresis (plasma exchange). It is characterised by thrombocytopaenia, microangiopathic haemolytic anaemia (schistocytes [fragmented RBCs] seen on peripheral smear), neurological findings, renal dysfunction, and fever
PRECAUTIONS:
General:
Clopidogrel bisulfate prolongs the bleeding time and therefore should be used with caution in patients who may be at risk of increased bleeding from trauma, surgery, or other pathological conditions (particularly gastrointestinal and intraocular). If a patient is to undergo elective surgery and an antiplatelet effect is not desired, clopidogrel bisulfate should be discontinued 5 days prior to surgery.
In patients with recent TIA or stroke who are at high risk for recurrent ischaemic events, the combination of aspirin and clopidogrel has not been shown to be more effective than clopidogrel alone, but the combination has been shown to increase major bleeding.
In CAPRIE, clopidogrel bisulfate was associated with a rate of gastrointestinal bleeding of 2.0% vs 2.7% on aspirin. In CURE, the incidence of major gastrointestinal bleeding was 1.3% vs 0.7% (clopidogrel bisulfate + aspirin versus placebo + aspirin, respectively). Clopidogrel bisulfate should be used with caution in patients who have lesions with a propensity to bleed (such as ulcers)
Laboratory Tests:
No tests in addition to routine ICU tests are indicated
Drug/Laboratory Test Interactions:
None noted
IMPORTANT DRUG INTERACTIONS IN ICU:
The risk of bleeding increases when clopidogrel is combined with other anticoagulants. Omeprazole and other PPIs decrease the antiplatelet effect of clopidogrel. It may be more appropriate to use Ranitidine as ulcer prophylaxis in patients on clopidogrel. If clopidogrel is used concomitantly with a PPI the dosages should be separated by 12 hours
ADVERSE REACTIONS:
Body as a Whole:
Bleeding, anaphylaxis, angioedema, serum sickness, fatigue
Haematological:
TTP, leucopenia, eosinophilia
Gastrointestinal System:
Pancreatitis, stomatitis, colitis
Respiratory System:
Interstitial pneumonitis, bronchospasm
Skin:
Rash