Pergolide
Pergolide mesylate
Also known as: Permax · Celance · Nopar · Parkotil · Parlide · Pharken · LY-127809 · pergolide mesilate · pergolidi mesilas
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Horses
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Equine 'Cushing's-like' Disease [pituitary pars intermedia dysfunction (PPID)] | Initial dose of 1 mg (total dose) per day for horses and ponies with PPID. If the horse owner is willing to administer half the dose twice daily, this may be preferable on the basis of recent pharmacokinetic data. If anorexia or temporary dullness develop, treatment should be halted for 2 days or until appetite improves, and then restarted at 0.25 mg per day for 2 days, 0.5 mg per day for 2 days, and 0.75 mg per day for 2 days. | PO | q24h or divided q12h | — | 🌎 NA |
| Equine 'Cushing's-like' Disease [pituitary pars intermedia dysfunction (PPID)] | 1.7-5.5 micrograms/kg | PO | Varies | — | 🌎 NA |
| Equine 'Cushing's-like' Disease [pituitary pars intermedia dysfunction (PPID)] | 0.002 mg/kg. If no improvement is noted within 8-12 weeks, the daily dose can be increased by 0.002 mg/kg monthly up to a total dose of 0.006 mg/kg (3 mg/day for a 500 kg horse). If only a limited response is observed with 0.006 mg/kg dose, addition of cyproheptadine (0.5 mg/kg PO q12h) to pergolide therapy is recommended. | PO | q24h | — | 🌎 NA |
- Equine 'Cushing's-like' Disease [pituitary pars intermedia dysfunction (PPID)]: Dose varies considerably. The higher doses are used in the more advanced cases or those refractory to treatment at a lower dose.
- Equine 'Cushing's-like' Disease [pituitary pars intermedia dysfunction (PPID)]: Usually, only transient anorexia is recognized during the initial week of treatment and can be overcome in time or by cutting the dose in half for 2-4 days.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Pergolide is an ergot-derivative dopamine agonist primarily used in veterinary medicine as the gold standard treatment for Pituitary Pars Intermedia Dysfunction (PPID), commonly known as Equine Cushing's Disease.
- Clinical Importance: It is the most effective medical therapy for managing the clinical signs of PPID in horses, such as hypertrichosis (delayed shedding/long hair coat), lethargy, muscle wasting, and laminitis.
- Availability: Because commercial human products were withdrawn from the US market in 2007 due to valvular heart disease risks in humans, pergolide for veterinary use is exclusively obtained via veterinary compounding pharmacies.
- Tolerance: It is generally very well tolerated in equines, though transient anorexia may occur upon initiation of therapy.
Mechanism of action
Pergolide acts as a potent, long-acting agonist at D1 and D2 dopamine receptors (estimated to be 10-1000 times more potent than bromocriptine).
- Mechanism in PPID: In healthy horses, the hypothalamus releases dopamine, which tonically inhibits the pituitary pars intermedia. In horses with PPID, there is a neurodegenerative loss of these dopaminergic neurons.
- Pathway: Pergolide replaces this lost dopamine tone → binds to D2 receptors on melanotropes in the pars intermedia → inhibits the hypersecretion of pro-opiomelanocortin (POMC) peptides (including ACTH, α-MSH, and CLIP).
- This reduction in POMC peptides normalizes endocrine function and alleviates the clinical signs associated with PPID.
Safety & warnings
Contraindications
- Hypersensitivity to pergolide or other ergot derivatives
Adverse effects
- Anorexia/decreased appetite (up to 10% of horses during the first week)
- Colic (rare)
- Diarrhea (rare)
- Lethargy (dogs)
- Vomiting (dogs)
- Hypertension (dogs)
- Ptosis (dogs)
Precautions
Safety in pregnant horses has not been established. May interfere with lactation due to its ergot-derivative nature. Compounded aqueous suspensions are highly unstable; they must be stored in dark containers, refrigerated, and discarded after 30 days or if any color change occurs.
Drug interactions
May decrease the effects of pergolide
May decrease the effects of pergolide
Monitoring
- Dexamethasone suppression test (baseline and at 4-8 weeks post pergolide therapy initiation, repeat in 4-8 weeks if dosage is adjusted)
- Blood glucose (baseline, and if abnormal repeat as per dexamethasone suppression test)
- Clinical signs (hair coat, weight, PU/PD, etc.)
- Periodic CBC and clinical chemistry panel
Pharmacokinetics
Half-life
Absorption
Horses: Rapidly absorbed following oral administration, with Tmax within 1 hour. Humans: Orally absorbed (estimated 60% bioavailable).
Distribution
Horses: Appears to be rapidly and widely distributed. Humans: 90% bound to plasma proteins.
Metabolism
Humans: At least 10 different metabolites have been identified, some of which are active.
Elimination
Humans: Principle route of elimination is via the kidneys.
Overdose
Limited information is available on pergolide overdoses.
- Potential effects: GI disturbances, CNS effects, seizures, and hypotension.
- Dogs: Accidental ingestion has resulted in vomiting, lethargy, hypertension, and ptosis.
- Treatment: Care is primarily supportive. Phenothiazines (dopamine antagonists) may be used to decrease CNS stimulation effects.
Available products
Formulations
- Compounded oral suspension
- Compounded capsules
- Compounded tablets
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store pergolide tablets in tight containers at room temperature (25°C; 77°F); excursions permitted to 15-30°C (59-86°F). Compounded pergolide formulations in aqueous vehicles should be stored in dark containers, protected from light, and refrigerated. Do not use more than 30 days after compounding. Formulations that have undergone a color change should be considered unstable and discarded.
Client information
Important: Pergolide manages Equine Cushing's Disease (PPID) but does not cure it. Treatment is typically required for the rest of the horse's life.
- Patience is Key: It may take several weeks to months to see noticeable improvements in your horse's hair coat, energy levels, and weight.
- Appetite Changes: Some horses may eat less during the first week of treatment. If this happens, contact your veterinarian; a temporary dose reduction usually resolves the issue.
- Storage Matters: If using a compounded liquid suspension, keep it in the refrigerator, protected from light. Discard it after 30 days or if it changes color, as the medication degrades quickly in water.
- Holistic Care: Proper nutrition, regular farrier care, and weight management are crucial alongside medication for the successful treatment of this disease.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.