Like all medicines, this medicine can cause side effects, although not everybody gets them.
Immediate medical attention: Patients should seek medical attention immediately if the following are experienced: fever, signs of infection or extreme tiredness; signs of liver problems such as jaundice, whether or not associated with bleeding which appears under the skin as red pinpoint dots and/or confusion (see Precautions); swelling in the mouth or skin disorders such as rashes and itching, blisters of the skin.
Bleeding: The most common side effect reported with clopidogrel is bleeding. Bleeding may occur as bleeding in the stomach or bowels, bruising, haematoma, nose bleed, blood in the urine. In a small number of cases, bleeding in the eye, inside the head, the lung or the joints has also been reported.
Prolonged bleeding when taking Clopidogrel: In case of cuts or injuries, it may take longer than usual for bleeding to stop. This is linked to the way the medicine works as it prevents the ability of blood clots to form. For minor cuts and injuries e.g., cutting oneself, shaving, this is usually of no concern. However, if the bleeding is concerning, patients should seek medical attention straightaway (see Precautions).
Other side effects: Common side effects (may affect up to 1 in 10 people): Diarrhoea, abdominal pain, indigestion or heartburn.
Uncommon side effects (may affect up to 1 in 100 people): Headache, stomach ulcer, vomiting, nausea, constipation, excessive gas in stomach or intestines, rashes, itching, dizziness, sensation of tingling and numbness.
Rare side effects (may affect up to 1 in 1000 people): Vertigo, enlarged breasts in males.
Very rare side effects (may affect up to 1 in 10,000 people): Jaundice; severe abdominal pain with or without back pain; fever, breathing difficulties sometimes associated with cough; generalised allergic reactions (for example, overall sensation of heat with sudden general discomfort until fainting); swelling in the mouth; blisters of the skin; skin allergy; stomatitis; decrease in blood pressure; confusion; hallucinations; joint pain; muscular pain; changes in taste or loss of taste of food.
Side effects with frequency not known (frequency cannot be estimated from the available data): Hypersensitivity reactions with chest or abdominal pain, persistent low blood sugar symptoms.
In addition, changes may be identified in the blood or urine test results.
Reporting of side effects: Side effects should be reported. This includes any possible side effects not previously listed. By reporting side effects, patients can help provide more information on the safety of this medicine.