Bromocriptin

Bromocriptine is the chemical name of active ingredient in Parlodel. Bromocriptine, a drug that mimics the action of the naturally occurring neurotransmitter dopamine, has a long history of use by body builders and life extension enthusiasts. The drug originally gained popularity due to its reputation for acting as a mild growth hormone secretagogue.

Bromocriptine is a dopamine agonist drug (meaning it acts like dopamine in the brain), primarily activating the dopamine D2 receptors.  It's main use is for the treatment of high prolactin, Parkinson's disease, and acromegaly; it was also used by bodybuilders in the 80's for it's GH releasing properties. However, it's metabolic effects are far greater than that.

Lately however, bromocriptine has gained prominence particularly as a weight loss agent. In genetically obese rats, bromocriptine normalizes metabolism and there are many good reasons to think it will do the same in humans. Bromocriptine has use during dieting (to minimize the negative adaptations), muscle gain when very lean, and may be beneficial post-steroid cycle. It may also be useful for diabetes treatment and may have pro-sexual effects.

Athletes and bodybuilders looking to use this drug for weight loss usually take the drug at a dosage of 2.5-5mg per day for cycles of 4-6 weeks.

Side Effects

As with the majority of drugs bromocriptine has a number of well characterized side effects that seem more unpleasant than dangerous, and often abate during treatment. These include nausea, orthostatic hypotension, headaches, abdominal discomfort, nasal congestion, fatigue and constipation. Besides these there are two other potential side effects that are not as well characterized, that are controversial, and that are of particular interest to bodybuilders and other athletes. The first I would like to address is the possibility that bromocriptine may lower testosterone levels in normal men, as well as increase the ovarian aromatization of testosterone to estrogen in women. The second is the potential bromocriptine may have to suppress the immune system in normal humans.