Nausea, stomach cramps, loss of appetite, diarrhea, dizziness, or headache may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor immediately if any of these unlikely but serious side effects occur: arm/leg/back pain, fast heartbeat, hair loss/color change, mental/mood changes (e.g., anxiety, depression, hallucinations), ringing in the ears/hearing loss, worsening of skin conditions (e.g., psoriasis). This medication may infrequently cause serious (sometimes permanent) eye problems or muscle damage, especially if you take it for a long time. Seek immediate medical attention if any of these unlikely but very serious side effects occur: sensitivity to light, vision changes (e.g., blurred vision, seeing light flashes/streaks/halos, missing/blacked-out areas of vision), muscle weakness. Tell your doctor immediately if any of these rare but very serious side effects occur: severe stomach/abdominal pain, severe nausea/vomiting, easy bleeding/bruising, signs of infection (e.g., fever, persistent sore throat), seizures, shortness of breath, swelling ankles/feet, extreme tiredness, dark urine, yellowing eyes/skin. A very serious allergic reaction is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.