Adult: Idiopathic or originating from a prolactin-secreting pituitary microadenoma or macroadenoma: Initially, 25 mcg daily for 3 days followed by 50 mcg daily for the next 3 days, then 75 mcg daily thereafter, then increase dose if needed at interval of at least 1 week, until optimal response is achieved. Usual maintenance dose: 75-150 mcg daily. For dose >300 mcg daily, increase in increments of 75-150 mcg daily at intervals of at least 4 weeks up to Max 900 mcg daily. All doses are given at bedtime.
Should be taken with food. Take w/ some food at bedtime.
Hepatic and renal impairment.
Patient with history or symptoms of psychotic disorders, Parkinson's disease. Women of child-bearing age. Pregnancy and lactation.
Significant: CNS depression (e.g. sudden sleep onset, somnolence), fertility changes (restoration of fertility), gastrointestinal distress (e.g. frequent nausea and vomiting), impulsive control disorders (e.g. pathological gambling, increased libido, hypersexuality, compulsive spending, binge and compulsive eating), hypotension. Rarely, acute psychosis. Gastrointestinal disorders: Nausea, vomiting, abdominal pain, constipation, diarrhoea. General disorders and admin site conditions: Fatigue. Metabolism and nutrition disorders: Anorexia, oedema. Nervous system disorders: Dizziness, headache. Psychiatric disorders: Insomnia. Respiratory, thoracic and mediastinal disorders: Nasal congestion. Vascular disorders: Flushing.
Patient Counseling Information
This drug may cause dizziness, drowsiness or somnolence, if affected, do not drive or operate machinery.
Monitor blood pressure (lying and standing) during the first days of therapy, prolactin levels, sedation, mental changes and development or symptoms of impulse control disorders.
Symptoms: Headache, dizziness, drowsiness, hypotension, possible collapse, severe nausea and vomiting, rarely hallucinations. Management: Symptomatic treatment. May give metoclopramide for emesis.
Reduced therapeutic effect with strong dopamine antagonist (e.g. neuroleptic agents). May enhance hypotensive effect of blood pressure lowering agents.
Reduced tolerability with alcohol.
Description: Quinagolide is a non-ergot selective dopamine D2-agonist which directly inhibits lactotroph cells in the anterior pituitary gland which are responsible for synthesis and secretion of prolactin. Onset: 2 hours. Duration: >24 hours. Pharmacokinetics: Absorption: Rapidly absorbed from the gastrointestinal tract. Bioavailability: 4%. Time to peak plasma concentration: 30-60 minutes. Distribution: Volume of distribution: Approx 100 L. Plasma protein binding: Approx 90%. Metabolism: Undergoes extensive metabolism in the liver via first-pass to active metabolite N-desethyl analogue and N,N-didesethyl analogue. Excretion: Via urine (50%); faeces (40%), both >95% as metabolites. Elimination half-life: 11.5 hours and approx 17 hours at steady state.