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Ergot alkaloid / Antimigraine Pregnancy: Contraindicated in women who are or may become pregnant (US Pregnancy Category X): oxytocic effect, maximal in the third trimester; prolonged uterine vasoconstriction may have contributed to fetal growth retardation in animals. Breastfeeding: ergotamine is excreted in breast milk and may cause vomiting, diarrhoea, weak pulse and unstable blood pressure in nursing infants — decide whether to discontinue nursing or the drug.

Ergotamine

Brand names: Ergomar

Adult dose

Dose: Vascular headache (e.g. migraine) attack: 2 mg (one sublingual tablet) at the first sign of an attack; another 2 mg tablet at half-hour intervals thereafter if necessary
Route: Sublingual — the tablet is placed under the tongue
Frequency: At the first sign of an attack (or to relieve symptoms after onset); another tablet at half-hour intervals if necessary, within the maximum dose limits
Max: Must not exceed three tablets in any 24-hour period; total weekly dosage should not exceed five tablets (10 mg) in any one week. The same label's patient information: no more than 2 tablets for any single migraine attack, and no more than 5 tablets in any 7-day period
Early administration gives maximum effectiveness. Not for chronic daily administration. Effective only for migraine headaches — not for other types of headache, and it lacks analgesic properties. Stay within the recommended dosage: most ergotism (intense arterial vasoconstriction with peripheral ischaemia, which can progress to gangrene) follows frank overdosage, but some cases have involved apparent hypersensitivity, and there are a few reports at doses within the recommended limits. Children: safety and effectiveness have not been established (US label). No UK SPC for ergotamine is listed on eMC — this dose is from US prescribing information (Ergomar Sublingual) and must be verified against UK practice.

Dose adjustments

Renal

Contraindicated in impaired renal function (US label).

Hepatic

Contraindicated in impaired hepatic function (US label).

Dose independently re-sourced from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Co-administration with potent CYP3A4 inhibitors — e.g. protease inhibitors (ritonavir, nelfinavir, indinavir), macrolides (erythromycin, clarithromycin, troleandomycin), ketoconazole, itraconazole — acute ergotism with vasospasm and ischaemia of the extremities, some cases resulting in amputation; rare reports of cerebral ischaemia with protease inhibitors, at least one fatal (CYP3A4-inhibitor co-administration is also the subject of the label's boxed warning)
  • Pregnancy, or women who may become pregnant (oxytocic effect; may cause fetal harm)
  • Peripheral vascular disease
  • Coronary heart disease
  • Hypertension
  • Impaired hepatic or renal function
  • Sepsis
  • Hypersensitivity to any of the components

Side effects

  • Serious vasoconstrictive complications: ischaemia, cyanosis, absence of pulse, cold extremities, gangrene — most common with long-term therapy at relatively high doses, but also reported with short-term or normal doses
  • Precordial distress and pain; ECG changes; muscle pains
  • Transient tachycardia or bradycardia; hypertension
  • Nausea and vomiting
  • Paraesthesia, numbness, weakness and vertigo
  • Localised oedema and itching
  • Fibrotic complications reported with ergotamine-with-caffeine therapy: retroperitoneal and/or pleuropulmonary fibrosis (a few reports); fibrotic thickening of heart valves with long-term continuous use (rare)
  • Rebound headache on stopping, after long-term indiscriminate use

Interactions

  • Potent CYP3A4 inhibitors (protease inhibitors, macrolide antibiotics, ketoconazole, itraconazole) — CONTRAINDICATED: raised ergotamine levels; serious or life-threatening peripheral and cerebral ischaemia
  • Less potent CYP3A4 inhibitors (saquinavir, nefazodone, fluconazole, fluoxetine, grapefruit juice, fluvoxamine, zileuton, metronidazole, clotrimazole) — potential risk of serious toxicity including vasospasm
  • Other vasoconstrictors — should not be given with ergotamine
  • Sympathomimetics (pressor agents) — may cause extreme elevation of blood pressure
  • Propranolol — reported to potentiate the vasoconstrictive action of ergotamine
  • Nicotine — may provoke vasoconstriction, predisposing to a greater ischaemic response

Monitoring

  • Patient advice in the label — report immediately: numbness or tingling in the fingers and toes, muscle pain in the arms and legs, weakness in the legs
  • Patient advice in the label — report immediately: chest pain, temporary speeding or slowing of the heart rate, swelling or itching

Reference: US FDA prescribing information (DailyMed) — Ergomar Sublingual (ergotamine tartrate); no UK SmPC is listed on eMC (checked 2026-10-08). Verify against your local formulary and current prescribing references before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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