Bromocriptine dosage

Bromocriptine mesilate is 2-bromo-a-ergocryptine methane-sulphonate or 2-bromo-12 -hydroxy-2,-(l-methylethyl)-5 -(2-methylpropyl-5 a-ergotaman-3, 6, 18-trione methanesulphonate or Bromocriptinum (INN). It is the active ingredient in Parlodel dosage forms. 

The identification of bromocriptine mesilate in the dosage form can be carried out by thin layer chromatography using Merck plates with dichloromethane/methanol/formic acid 78 20 2 (v/v/v) and subsequent uv-visualization at 254 and 360 nm. Using this method, it is important to only air-dry the spot after application to the plate, since more vigorous evaporation of the solvent will give rise to artifacts (32). 

Bromocriptine can also be identified as the base by ir spectroscopy after extraction from the dosage form with ethanol and removal of the solvent, both in solution and in a KBr pellet (33). ... 

A specific assay of bromocriptine mesilate in the dosage form may be carried out by tic followed by uv-spectrophotometry (26)(The system can also serve for identification purposes). The drug substance is extracted with methanol in the absence of light, the chromatographic conditions are Merck plates F 254, mobile phase dichloromethane/dioxane/ ethanol abs./conc. ammonia 180 15 5 0.1 per volume. 

A further specific assay is the HPLC-determination of bromocriptine mesilate following extraction with methanol from the dosage form using RP-18 as the stationary and aceto-nitrile/0.01 M ammonium carbonate solution 65 35 as the mobile phase. Uv-detection wavelength is set at 300 nm (26). 

The safety of bromocriptine has not been demonstrated in dosages exceeding 100 mg/day. 

Increased sexual drive in patients with Parkinson s disease is common, but bromocriptine can also cause impotence, which can respond to dosage reduction (SEDA-13, 111). 

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 associated with bromocriptine therapy inclnde central nervous system symptoms such as headache, lightheadedness, dizziness, nervousness, and fatigue. Gastrointestinal effects such as nausea, abdominal pain, and diarrhea are also common. Bromocriptine should be administered with food to decrease the incidence of adverse gastrointestinal effects. Although most of these adverse effects diminish with continued treatmenfi about 12% of patients will not tolerate the adverse effects associated with bromocriptine therapy. Vaginal preparations of bromocriptine have been studied in an effort to decrease the incidence of adverse effects associated with oral dosage forms. ... 

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