Among the most common side effects in lithium therapy is tremor, principally noticed in the fingers (Table 5–2). It resembles intentional, coffee-induced, or familial tremor in frequency, being faster than pseudoparkinsonian tremor. When tremor is severe enough to affect handwriting, the writing is usually jagged and irregular, but not micrographic as in parkinsonism. Tremor sometimes is worse at peak lithium blood level and can be ameliorated by dosage rearrangement. Dosage reduction can often be used to bring the blood level low enough to make tremor either absent or mild and inconspicuous. If there is good reason to maintain a serum lithium level that causes a disturbing degree of tremor, propranolol at dosages ranging from 10 to 160 mg/day can be used to reduce the tremor.