Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision or vision changes; chest pain; confusion; fainting; fast or irregular heartbeat; flu-like symptoms (fever, chills, sore throat); one-sided weakness; pale skin color; redness, tenderness, or swelling of the calf; seizures; severe diarrhea, dizziness, headache, stomach pain, or vomiting; severe or persistent tiredness or weakness; slurred speech; sudden pain or numbness of an arm or leg; sudden shortness of breath; sudden trouble walking or loss of balance; swelling of the arms or legs; vision or speech problems; weight gain.
Symptoms of dystonia , prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment. Dystonic symptoms include: spasm of the neck muscles, sometimes progressing to tightness of the throat, swallowing difficulty, difficulty breathing, and/or protrusion of the tongue. While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups.
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