Drowsiness, dizziness, constipation, blurred vision, or dry mouth may occur. If any of these effects persist or worsen, notify your doctor. Some people, especially children, may experience excitability rather than drowsiness. 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. This medication can cause severe tissue damage, possibly requiring surgery. Tell your doctor/nurse immediately if you experience burning, pain, redness, swelling, or numbness at or near the injection site. Tell your doctor immediately if any of these unlikely but serious side effects occur: lack of coordination, severe dizziness, fainting, slow/fast heartbeat, muscle stiffness, involuntary muscle movements, muscle spasms (e.g., rolling eyes, twisting neck/back), restlessness, decreased/painful urination. Seek immediate medical attention if any of these unlikely but very serious side effects occur: slow/shallow breathing, difficulty waking up, hot/dry skin. Tell your doctor immediately if any of these rare but very serious side effects occur: signs of serious infection (e.g., persistent sore throat, fever), unusual bleeding/ bruising, severe stomach/abdominal pain, yellowing of eyes/skin, dark urine. This drug may infrequently cause a very serious (rarely fatal) nervous system disorder (neuroleptic malignant syndrome). If you notice any of the following unlikely but very serious side effects, seek immediate medical attention: severe muscle stiffness, mental/mood changes (e.g., confusion, extreme drowsiness), high fever, seizures, irregular/fast heartbeat, increased sweating. A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe 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.