Nausea, vomiting, dyspepsia, obstipation, fatigue, sedation, dizziness, pruritus, sweating, flushing, dry mouth, headache. Posterior reversible encephalopathy syndrome (PRES) & reversible cerebral vasoconstriction syndrome (RCVS) w/ symptoms eg, sudden severe headache, nausea, vomiting, confusion, seizures &/or visual disturbances.