Ergomar Drug Interactions: What to Avoid and What to Tell Your Doctor

Ergomar (ergotamine tartrate) has one of the more complex drug interaction profiles of any commonly prescribed migraine medication. Some interactions are merely important to monitor; others are contraindicated and can be life-threatening. Before taking Ergomar, it's essential to share your full medication list with your prescriber and pharmacist.

This guide covers the most important Ergomar drug interactions—from contraindicated combinations to drugs that require extra caution.

The Boxed Warning: CYP3A4 Inhibitors Are Contraindicated

Ergomar carries a boxed warning—the FDA's strongest warning—regarding interactions with potent CYP3A4 inhibitors. Here's what that means:

Ergotamine is metabolized in the liver primarily by the CYP3A4 enzyme. When you take a drug that inhibits this enzyme—a CYP3A4 inhibitor—ergotamine cannot be broken down properly, causing its blood levels to rise dangerously high. The result can be ergotism: a severe condition involving life-threatening peripheral ischemia (loss of blood flow to the hands, feet, and brain) that has resulted in amputations and deaths.

Drugs That Are CONTRAINDICATED With Ergomar

Do NOT use Ergomar if you are currently taking any of the following:

Macrolide antibiotics: Clarithromycin (Biaxin), erythromycin, troleandomycin — commonly prescribed for respiratory and sinus infections

HIV protease inhibitors: Ritonavir (Norvir), nelfinavir, indinavir — boosters and antiretrovirals used in HIV treatment regimens

Cobicistat-containing regimens: Stribild, Genvoya, Prezcobix, and other regimens containing cobicistat as a pharmacokinetic booster

Azole antifungals: Ketoconazole, itraconazole (Sporanox) — prescribed for fungal infections

Other vasoconstrictors: Do not combine Ergomar with other vasoconstrictive drugs, as this can cause extreme and dangerous elevation of blood pressure

Norepinephrine: Additive vasospasm; contraindicated

Nitroglycerin (all forms): Ergotamine antagonizes the vasodilating effects of nitrates, making nitroglycerin ineffective for angina and potentially worsening cardiovascular outcomes

Triptans: Separate by 24 Hours (72 Hours for Eletriptan)

Triptans and Ergomar both constrict cranial blood vessels. Using them within too short a window can cause dangerously additive vasospasm, potentially triggering a heart attack or stroke.

Sumatriptan (Imitrex), rizatriptan (Maxalt), zolmitriptan (Zomig), almotriptan (Axert), naratriptan (Amerge), frovatriptan (Frova): Do not use within 24 hours of Ergomar in either direction

Eletriptan (Relpax): Do not use within 72 hours of Ergomar (stricter separation due to eletriptan's own CYP3A4 metabolism)

Medications That Require Caution (Not Contraindicated, But Risky)

Beta-blockers (propranolol/Inderal, atenolol, metoprolol): Beta-blockers block the vasodilating effects of epinephrine, leaving ergotamine's vasoconstrictive effects unopposed. This can significantly potentiate vasoconstriction. Use with caution; monitor for peripheral ischemia symptoms.

SSRIs (fluoxetine/Prozac, paroxetine/Paxil, fluvoxamine): Some SSRIs are mild CYP3A4 inhibitors and may modestly increase ergotamine levels. Monitor for increased side effects.

Sympathomimetics (pseudoephedrine, phenylephrine): Additive vasopressor effects; can cause extreme elevation of blood pressure. Avoid concurrent use with decongestants.

Nefazodone (antidepressant): Potent CYP3A4 inhibitor; avoid concurrent use.

Mifepristone: CYP3A4 inhibitor; avoid concurrent use.

Food and Supplement Interactions

Grapefruit and grapefruit juice: Grapefruit inhibits intestinal CYP3A4, which can raise ergotamine blood levels. Avoid grapefruit and grapefruit juice while taking Ergomar.

Nicotine (tobacco, vaping, patches, gum): Nicotine provokes vasoconstriction independently, which adds to ergotamine's vasoconstrictive effects. Smoking while on Ergomar significantly increases the risk of ischemic complications.

What to Tell Your Doctor and Pharmacist

Before taking Ergomar, make sure your prescriber and pharmacist know about:

All prescription medications, including antiretrovirals, antibiotics, antifungals, and antidepressants

Over-the-counter medications, especially decongestants containing pseudoephedrine or phenylephrine

Any other migraine medications, particularly triptans

Supplements (St. John's Wort can affect CYP3A4 metabolism)

Tobacco or nicotine use

Your pharmacist performs a drug interaction check with every prescription fill. However, supplements and OTC medications may not be in your pharmacy's system unless you tell them.

The Bottom Line

Ergomar's interaction profile—particularly the CYP3A4 inhibitor contraindications—requires careful medication review before prescribing or taking it. The interactions with macrolide antibiotics and HIV antiretrovirals are the most dangerous and have resulted in serious harm. For a complete overview of side effects, see: Ergomar Side Effects: What to Expect and When to Call Your Doctor. To find Ergomar at a nearby pharmacy, visit medfinder.