Parlodel (bromocriptine mesylate) represents a cornerstone in the management of hyperprolactinemic disorders, offering targeted dopamine receptor agonism to restore endocrine balance. As a first-generation ergot derivative, it effectively suppresses prolactin secretion from the anterior pituitary gland, addressing both the biochemical abnormalities and clinical manifestations associated with elevated prolactin levels. Its well-established efficacy profile and decades of clinical use make it a trusted option for endocrinologists and neurologists managing complex hormonal and movement disorders.

Features

• Active ingredient: Bromocriptine mesylate
• Mechanism: Dopamine D2 receptor agonist
• Formulations: 2.5mg tablets and 5mg capsules
• Half-life: Approximately 15 hours
• Metabolism: Hepatic, via cytochrome P450 system (primarily CYP3A4)
• Excretion: Primarily biliary (85-98%)
• Bioavailability: 28% when taken with food (compared to 6-7% fasting)

Benefits

• Rapid normalization of elevated prolactin levels, typically within weeks of initiation
• Restoration of gonadal function and fertility in both men and women with hyperprolactinemia
• Reduction or elimination of galactorrhea in appropriate patients
• Effective control of Parkinson’s disease symptoms at higher doses through dopaminergic stimulation
• Prevention of pituitary tumor growth in prolactin-secreting adenomas
• Established safety profile with extensive clinical experience spanning decades

Common use

Parlodel is primarily indicated for the treatment of hyperprolactinemia associated with pituitary adenomas (prolactinomas) or idiopathic hyperprolactinemia. It is effective in managing galactorrhea, amenorrhea, infertility, and hypogonadism resulting from elevated prolactin levels. In neurological practice, it is used as adjunctive therapy in Parkinson’s disease, helping to manage motor symptoms through its dopaminergic activity. Off-label uses include management of neuroleptic malignant syndrome and acromegaly (though other dopamine agonists are now preferred for acromegaly).

Dosage and direction

For hyperprolactinemia: Initiate therapy with 1.25-2.5mg daily, preferably with food to enhance absorption and minimize gastrointestinal side effects. The dosage may be gradually increased by 2.5mg increments at 3-7 day intervals until optimal therapeutic response is achieved. Most patients respond to doses between 2.5-15mg daily, divided into two or three administrations.

For Parkinson’s disease: Begin with 1.25mg twice daily, increasing gradually by 2.5mg increments every 2-4 weeks. Maintenance doses typically range from 10-40mg daily in divided doses.

Administration should occur with food, and patients should be advised to maintain consistent timing of doses to ensure stable drug levels. Dose titration should be performed under medical supervision, with regular monitoring of prolactin levels in endocrine applications.

Precautions

Cardiovascular monitoring is recommended during initial dose titration due to potential hypotensive effects. Patients should be cautioned about the possibility of syncope, particularly during the first few days of therapy. Regular ophthalmologic examinations are advised for patients on long-term therapy to monitor for potential retinal changes. Hepatic and renal function should be assessed periodically, with dose adjustments considered in patients with significant impairment. Patients should be advised about potential drowsiness and warned against operating machinery or driving until their response to the medication is established. Alcohol should be avoided due to enhanced sedative effects.

Contraindications

Parlodel is contraindicated in patients with hypersensitivity to ergot alkaloids or any component of the formulation. It should not be used in patients with uncontrolled hypertension, toxemia of pregnancy, or coronary artery disease. Contraindications include severe ischemic heart disease, peripheral vascular disorders, and history of psychotic disorders. Use is prohibited in patients taking macrolide antibiotics (except azithromycin), protease inhibitors, or nefazodone due to significant drug interactions. The medication is contraindicated in patients with valvular heart disease or history of fibrotic disorders.

Possible side effect

Common adverse effects (>10%) include nausea, headache, dizziness, fatigue, and orthostatic hypotension. Gastrointestinal disturbances such as vomiting, abdominal cramps, and constipation occur frequently during initial therapy. Less common effects (1-10%) include nasal congestion, digital vasospasm, and sleep disturbances. Serious but rare side effects (<1%) include pleural effusion, pleural fibrosis, pericarditis, and cardiac valvulopathy. Psychiatric effects including confusion, hallucinations, and impulse control disorders have been reported, particularly at higher doses used for Parkinson’s disease. Sudden sleep attacks without warning have been documented in some patients.

Drug interaction

Significant interactions occur with CYP3A4 inhibitors including macrolide antibiotics (except azithromycin), antifungal agents (ketoconazole, itraconazole), protease inhibitors, and nefazodone, which may increase bromocriptine levels and toxicity. Concomitant use with other dopamine antagonists (metoclopramide, phenothiazines, butyrophenones) may diminish therapeutic efficacy. Hypotensive effects may be potentiated by antihypertensive medications, nitrates, and alcohol. Serotonin syndrome has been reported when used with SSRIs, SNRIs, or triptans. Dopamine antagonists used for psychosis may require dose adjustment when co-administered with Parlodel.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not double the dose to make up for a missed administration. Consistent timing is important for maintaining stable prolactin suppression in endocrine applications and stable dopaminergic effects in neurological use.

Overdose

Symptoms of overdose may include severe nausea, vomiting, hypotension, confusion, hallucinations, and syncope. Management involves immediate gastric lavage if ingestion was recent, followed by activated charcoal administration. Cardiovascular support with intravenous fluids and vasopressors may be necessary for hypotension. Symptomatic treatment should be provided, with close monitoring of vital signs and cardiac function. There is no specific antidote for bromocriptine overdose. Dialysis is unlikely to be effective due to extensive protein binding and large volume of distribution.

Storage

Store at controlled room temperature (20-25°C or 68-77°F) in the original container, protected from light and moisture. Keep tightly closed and away from excessive heat or humidity. Do not store in bathroom cabinets where moisture levels may fluctuate. Keep out of reach of children and pets. Do not use after the expiration date printed on the packaging. Proper disposal of unused medication should follow local regulations for pharmaceutical waste.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Parlodel is a prescription medication that should be used only under the supervision of a qualified healthcare professional. Individual response to therapy may vary, and treatment decisions should be based on comprehensive medical evaluation. Patients should consult their healthcare provider for personalized medical advice and report any adverse effects promptly. The full prescribing information should be reviewed before initiating therapy.

Reviews

Clinical studies demonstrate Parlodel’s efficacy in normalizing prolactin levels in 70-80% of patients with microprolactinomas and 60-70% of those with macroprolactinomas. Long-term follow-up studies show maintained efficacy in approximately 85% of patients with appropriate dose titration. In Parkinson’s disease, it provides significant improvement in motor scores, though its use has declined with the availability of newer agents. Patient satisfaction surveys indicate good tolerability with appropriate dose escalation, though gastrointestinal side effects remain a common reason for discontinuation in the initial treatment phase. Many endocrinologists consider it a valuable first-line option despite the availability of newer dopamine agonists due to its extensive safety database and cost-effectiveness.