Bromocriptine, a specific dopamine receptor agonist, has been used for the treatment of various hyperprolactinemic conditions and as adjunctive therapy for acromegaly (with or without concomitant hyperprolactinemia) and Parkinson's disease. Bromocriptine is extremely effective in suppressing prolactin secretion regardless of the cause, in restoring gonadal function and fertility, and in decreasing the size of prolactin-secreting pituitary tumors. Most patients with acromegaly have clinical improvement with this drug. When bromocriptine is added to a regimen of levodopa or carbidopa, patients with Parkinson's disease frequently have additional clinical improvement and, in most patients, the levodopa or carbidopa dose can be reduced. Withdrawal of bromocriptine therapy is associated in most patients with reversal of its beneficial effects—return of hyperprolactinemia, return of excess growth hormone secretion, and exacerbation of Parkinson's disease.