Side Effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Also, because of the way these medicines act on the body, there is a chance that they might cause other unwanted effects that may not occur until months or years after the medicine is used. These delayed effects may include certain types of cancer, such as leukemia. Discuss these possible effects with your doctor.
Check with your doctor immediately if any of the following side effects occur:
More common- Black, tarry stools
- Blood in urine or stools
- Cough or hoarseness
- Fever or chills
- Inflammation of the mouth
- Lower back or side pain
- Painful or difficult urination
- Pinpoint red spots on skin
- Unusual bleeding or bruising
- Chest pain
- Dizziness
- Fast or irregular breathing
- Joint pain
- Light-headedness
- Puffiness or swelling around face
- Rapid heartbeat
- Shortness of breath
- Sudden, severe decrease in blood pressure
- Sweating
- Swelling of fingers, hands, arms, lower legs, or feet
- Sweating
- Tingling in lower legs, hands, or feet
- Blurred vision
- Difficulty swallowing
- Heartburn
- Severe upper abdominal and back pain
- Vomiting blood
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common- Abdominal pain
- Anxiety
- Diarrhea
- General fatigue or muscle pain
- Headache
- Missed or irregular menstrual periods
- Loss of appetite
- Nausea and vomiting
- Rash
- Trouble in sleeping
- Weight loss (sudden)
- Bloody nose
- Confusion
- Constipation
- Darkening of skin
- Depression
- Dry mouth
- Inflammation at place of injection
- Itching
- Sore throat or cough
- Stuffy nose, runny nose, or sneezing
After you stop using this medicine, it may still produce some side effects that need attention. During this period of time, check with your doctor immediately if you notice the following side effects:
- Black, tarry stools
- Blood in urine or stools
- Cough or hoarseness, accompanied by fever or chills
- Fever or chills
- Lower back or side pain, accompanied by fever or chills
- Painful or difficult urination, accompanied by fever or chills
- Pinpoint red spots on skin
- Shortness of breath
- Unusual bleeding or bruising
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.


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