>10% Ataxia (15%),Dizziness (44%),Drowsiness (32%),Nausea (29%),Vomiting (18%) 1-10% Dry mouth (8%) Rare MI,Stevens-Johnson syndrome Hepatic failure,Punctate cortical lens opacities,Syndrome of inappropriate antidiuretic hormone secretion (SIADH) Frequency Not Defined Hemopoietic system: Aplastic anemia, agranulocytosis, pancytopenia, bone marrow depression, thrombocytopenia, leukopenia, leukocytosis, eosinophilia, anemia, acute intermittent porphyria, variegate porphyria, porphyria cutanea tarda Skin: Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) (see Black Box Warnings), pruritic and erythematous rashes, urticaria, photosensitivity reactions, alterations in skin pigmentation, exfoliative dermatitis, erythema multiforme and nodosum, purpura, aggravation of disseminated lupus erythematosus, alopecia, diaphoresis, and onychomadesis Cardiovascular system: Congestive heart failure, edema, aggravation of hypertension, hypotension, syncope and collapse, aggravation of coronary artery disease, arrhythmias and AV block, thrombophlebitis, thromboembolism, and adenopathy or lymphadenopathy Liver: Abnormalities in liver function tests, cholestatic and hepatocellular jaundice, hepatitis; very rare cases of hepatic failure Pancreatic: Pancreatitis Respiratory System: Pulmonary hypersensitivity characterized by fever, dyspnea, pneumonitis, or pneumonia Genitourinary System: Urinary frequency, acute urinary retention, oliguria with elevated blood pressure, azotemia, renal failure, and impotence (rare reports of impaired male fertility and/or abnormal spermatogenesis) Laboratory: Albuminuria, glycosuria, elevated BUN, decreased plasma calcium, and microscopic deposits in the urine Nervous system: Dizziness, drowsiness, disturbances of coordination, confusion, headache, fatigue, blurred vision, visual hallucinations, transient diplopia, oculomotor disturbances, nystagmus, speech disturbances, abnormal involuntary movements, peripheral neuritis and paresthesias, depression with agitation, talkativeness, tinnitus, hyperacusis, neuroleptic malignant syndrome; isolated cases of neuroleptic malignant syndrome Digestive system: Nausea, vomiting, gastric distress and abdominal pain, diarrhea, constipation, anorexia, and dryness of the mouth and pharynx, including glossitis, and stomatitis Eyes: Scattered punctate cortical lens opacities, increased intraocular pressure as well as conjunctivitis Musculoskeletal system: Aching joints and muscles, and leg cramps Metabolism: Fever and chills; SIADH; cases of frank water intoxication, with decreased serum sodium (hyponatremia) and confusion; decreased levels of plasma calcium leading to osteoporosis Potentially Fatal: Agranulocytosis, aplastic anaemia, hepatic failure, severe exfoliative dermatitis and Stevens-Johnson syndrome.