Bromocriptine adverse effects

Bromocriptine directly binds to the D2 receptors on the lac-totroph cells to exert its effect. Bromocriptine normalizes prolactin level, restores menstrual cycles, and reduces tumor size in approximately 90% of patients.49 Adverse effects such as nausea, dizziness, and orthostatic hypotension often limit 5% to 10% of patients from continuing treatment. Thus, start bromocriptine at a low dose (e.g., 0.625-1.25 mg) at bedtime... 

Dopamine receptor agonists. Deficient dopaminergic transmission in the striatum can be compensated by ergot derivatives (bromocriptine p. 114], lisu-ride, cabergoline, and pergolide) and nonergot compounds (ropinirole, prami-pexole). These agonists stimulate dopamine receptors (D2, D3, and D sub-types), have lower clinical efficacy than levodopa, and share its main adverse effects. 

At least as effective as bromocriptine in the treatment of advanced parkinsonian patients with levodopa-related motor fluctuations adverse effects similar in incidence and severity appears to lack some of the toxicity seen with bromocriptine, pergolide, and cabergoline (e.g., pleuropulmonary disease) may be a useful alternative in patients with intolerable adverse effects due to ergot derivatives... 

Bromocriptine is a D2 agonist its structure is shown in Table 16-6. This drug has been widely used to treat Parkinson s disease in the past, but is now rarely used for this purpose, having been superseded by the newer dopamine agonists. Bromocriptine is absorbed to a variable extent from the gastrointestinal tract peak plasma levels are reached within 1-2 hours after an oral dose. It is excreted in the bile and feces. The usual daily dose of bromocriptine for parkinsonism varies between 7.5 and 30 mg. To minimize adverse effects, the dose is built up slowly over 2 or 3 months from a starting level of 1.25 mg twice daily after meals the daily dose is then increased by 2.5 mg every 2 weeks, depending on the response or the development of adverse reactions. 

Bromocriptine Therapy of hyperprolactinemia Oral tablet and vaginal suppository Proved to be effective and safe, without the adverse effects of oral administration vaginal suppository obtained higher reduction in serum prolactin 330... 

When the manufacturers examined reports from physicians on adverse effects from bromocriptine in inhibition of lactation, there were 38 cases of seizures (9). 

Because of its use in the treatment of female infertility, which inevitably involves early exposure of some embryos, the safety of bromocriptine in early pregnancy has been systematically evaluated in a large multicenter study with prolonged follow-up (SEDA-13, 112). There was no evidence that this use of bromocriptine was associated with an increased risk of spontaneous abortion, multiple pregnancy, or the occurrence of congenital malformations nor did exposure in utero seem to have any adverse effects on postnatal development. Cervical incompetence may be a problem at the time of delivery, but this may well be due to a long history of infertility rather than to the drug itself. 

Tamoxifen can resolve some of bromocriptine s adverse effects, offering the possibility of bromocriptine treatment to patients who cannot otherwise tolerate it (SEDA-8,144). 

Jenkins PJ, Jain A, Jones SL, Besser GM, Grossman AB. Oral prednisolone supplement abolishes the acute adverse effects following initiation of depot bromocriptine therapy. Clin Endocrinol (Oxf) 1996 45(4) 447-51. 

Fabre N, Montastruc JL, Rascol O. Alopecia an adverse effect of bromocriptine. CUn Neuropharmacol 1993 16(3) 266-8. 

Mesulergine is an 8-alpha-aminoergoline derivative that acts as a dopamine receptor agonist. In a blind, crossover study in six patients with hyperprolactinemia, mesulergine 0.5 mg caused fewer adverse effects than bromocriptine 2.5 mg, while the prolactin release-inhibitory effect of the two was of the same order (1). 

The adverse effects of pergolide, a dopamine receptor agonist, resemble those of bromocriptine (SEDA-10, 118) (SEDA-13,113). 

A recommended initial dose of pergolide (which is about 13 times more potent than bromocriptine) is 0.05 mg/day for 2 days, gradually increasing the dose by approximately 0.1-0.15 mg/day every 3 days over a 12-day period. Should more drug be needed, the dose then may be increased by 0.25 mg every 3 days until symptoms are eliminated or adverse effects occur. The mean therapeutic dose in most clinical trials was approximately 3 mg/day. 

Pramipexole is initiated at a dose of 0.125 mg three times a day and increased every 5 to 7 days as tolerated. In a fixed-dose study, daily doses of 3, 4.5, and 6 mg were not more effective than 1.5 mg/day, and the higher doses were associated with a higher frequency of adverse effects. When switching from bromocriptine or pergolide to pramipexole, a 10 1 and 1 1 dosage substitution is recommended, respectively. Ropinirole is initiated at 0.25 mg three times a day and increased by 0.25 mg three times a day on a weekly basis to a maximum of 24 mg/day. The dose of dopaminergic agonists is best determined by slow titration to enhance tolerance and to find the least dose that provides optimal benefit. 

The most common adverse effects of bromocriptine therapy include central nervous system symptoms such as headache, lightheadedness, dizziness, nervousness, and fatigue. Gastrointestinal effects such as nausea, abdominal pain, or diarrhea also are very common. Some patients may need to take bromocriptine with food to decrease the incidence of adverse gastrointestinal effects. Most adverse effects are seen early in the course of therapy and tend to decrease with continued treatment. Bromocriptine may cause thickening of bronchial secretions and nasal congestion. There have been rare cases of psychiatric disturbances, pleural diseases, and an erythromeMgic syndrome... 

For the management of hyperprolactinemia, bromocriptine therapy is typically initiated at a dose of 1.25 to 2.5 mg once daily at bedtime to minimize adverse effects. The dose can be gradually increased by 1.25-mg increments every week to obtain desirable serum prolactin concentrations. Usual therapeutic doses of bromocriptine range from 2.5 to 15 mg per day, although some patients may require doses as high as 40 mg per day. Bromocriptine is usually administered in two or three divided doses, but once-daily dosing has also been shown to be effective. ... 

The use of dopaminergic agents in combination with antimuscarinic drugs is common in the treatment of parkinsonism. Bromocriptine does not complicate treatment with antimuscarinic drugs or amantadine. If combined with levodopa, bromocriptine should be used in reduced doses to avoid intolerable adverse effects. Confusion, delusions, and hallucinations occur more frequently with bromocriptine than with levodopa. Bromocriptine does not require bioactivation for its antiparkinson effects. The answer is (C). 

The signs and symptoms described are those of etythromelalgia, an adverse effect of bromocriptine. The distal extremities (feet and hands) are usually involved. Arthralgia may occur along with the signs described. The answer is (C). 

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