Nifedipine and Nitroglycerin Ointments (for Fissures — Not Hemorrhoids)

This page exists specifically to prevent a common mix-up: nifedipine and nitroglycerin ointments are standard treatment for chronic anal fissures — they are not hemorrhoid treatments, and applying them for a hemorrhoid instead of a fissure targets the wrong mechanism entirely.

Key takeaways

Both medications relax the internal anal sphincter muscle, addressing the spasm that keeps a chronic fissure from healing.
Hemorrhoids don’t involve this same sphincter spasm mechanism, so these medications don’t have the same rationale for use there.
If you’re not sure whether you have a fissure or a hemorrhoid, that distinction matters directly for which of these treatments — if either — is appropriate.

Why these medications exist and what they treat

A chronic anal fissure is kept open partly by spasm and excess tone in the internal anal sphincter muscle, which reduces blood flow to the fissure and slows healing (see Anal fissure vs. hemorrhoid). Nifedipine and nitroglycerin (glyceryl trinitrate) both relax this muscle, improving blood flow to the area and allowing the fissure to heal — this is the specific, targeted mechanism behind their use.

Why this doesn’t apply to hemorrhoids

Hemorrhoids are swollen venous tissue, not a spasming sphincter muscle holding a wound open. The mechanism these medications address — relaxing sphincter spasm to improve blood flow to a fissure — isn’t the problem in a straightforward hemorrhoid. Using one of these medications for a hemorrhoid instead of a fissure isn’t targeting the right mechanism, which is part of why an accurate diagnosis matters before starting either treatment.

Nifedipine vs. nitroglycerin

Both are used similarly for chronic anal fissures, generally as a topical ointment or cream:

Nitroglycerin (glyceryl trinitrate) is a vasodilator; a notable side effect is headache, which causes some people to discontinue it.
Nifedipine (or the related calcium channel blocker diltiazem) works through a different pathway to achieve a similar relaxing effect, generally with a different side-effect profile — some studies suggest a higher healing rate with nifedipine compared to nitroglycerin, though results vary between studies, and either may be recommended first depending on your doctor’s judgment and your individual situation.

How these are typically prescribed

These are generally prescription treatments for a diagnosed chronic fissure (present longer than about 6–8 weeks), used after initial conservative measures (fiber, sitz baths) haven’t resolved things on their own. They are not typically first-line for an acute fissure, which often heals with conservative measures alone.

What comes next if these don’t work

If topical medication doesn’t resolve a chronic fissure, options include botulinum toxin (Botox) injection into the sphincter, or a minor surgical procedure (lateral internal sphincterotomy) for cases that don’t respond to less invasive treatment.

When to see a doctor

Sharp, tearing pain during and after bowel movements lasting more than a few weeks (suggesting a chronic fissure) rather than typical hemorrhoid symptoms
Confirmation of which condition you actually have, before starting either of these medications
A fissure that hasn’t healed with initial conservative measures

Not sure if you have a fissure or a hemorrhoid? See Anal fissure vs. hemorrhoid.

This page is for general education. These are prescription medications requiring a doctor’s diagnosis and guidance — not something to self-select based on symptoms alone.