Nifedipine, diltiazem or nitroglycerin: which fissure ointment should you choose?

What do nifedipine, diltiazem and nitroglycerin have in common?

All three do the same job by different routes: they lower the resting pressure of the internal anal sphincter, the involuntary muscle whose spasm keeps a chronic fissure open. With the muscle relaxed, blood reaches the back of the anal canal again and the tear can heal.

• Nifedipine and diltiazem are calcium channel blockers. They stop calcium from entering the muscle cells, and without calcium the muscle cannot hold its contraction. Both are old blood pressure drugs; on the anus they are used in low-strength ointments or gels.
• Nitroglycerin (glyceryl trinitrate, GTN) is a nitric oxide donor. Nitric oxide is the body’s own relaxing signal for smooth muscle.

They share the same rules of use: applied at or just inside the anal opening, two to three times a day, for 6 to 8 weeks, alongside fiber, water and sitz baths. All three need a prescription in the US, UK, Australia and India. And all three have the same weakness: when you stop, the sphincter returns to its old tone, so if stools are still hard the fissure can open again. For the underlying mechanism, see our treatment overview.

Which ointment heals more fissures?

Less difference than most people expect. What the evidence in our source library shows:

• Diltiazem vs nitroglycerin: a systematic review of seven randomized trials and 481 patients found no difference in healing between the two (Sajid, 2013).
• Calcium channel blockers vs nitroglycerin: the Cochrane review of non-surgical therapy concluded that calcium channel blockers are as effective as nitroglycerin, while nitroglycerin itself is only modestly better than placebo (48.9 % versus 35.5 % healing).
• Nifedipine: in a randomized double-blind trial in chronic fissures, nifedipine 0.3 % with lidocaine 1.5 % healed 94.5 % at 6 weeks against 16.4 % in the control group (Perrotti, 2002). In acute fissures, a nifedipine 0.2 % gel achieved remission in 95 % at 21 days against 50 % with lidocaine plus hydrocortisone (Antropoli, 1999).

Read those nifedipine numbers with care. They come from trials that compared it with a non-relaxing control ointment, not with nitroglycerin or diltiazem, so they look better than the head-to-head reviews. No source in our library compares nifedipine and diltiazem directly. Guidelines treat the two as interchangeable members of the same class, and in clinic we see them behave that way.

Recurrence is where nitroglycerin falls behind: about half of fissures healed with it come back, according to Cochrane, and diltiazem had fewer recurrences than nitroglycerin in the systematic review.

Which one has fewer side effects?

This is where the three really separate.

• Nitroglycerin: headache in up to half of patients, often with lightheadedness on standing and flushing. It cannot be combined with sildenafil, tadalafil or vardenafil. The headache is the main reason people stop it early; Nitroglycerin ointment for anal fissure: does it work, and can you live with the headache? explains how to manage it.
• Diltiazem: headache is much less common (risk ratio 0.39 against nitroglycerin). The typical complaint is local: itching or irritation of the skin around the anus, which usually settles with good hygiene and a thin barrier cream on the outer skin.
• Nifedipine: a similar profile to diltiazem, with occasional mild burning on application. Combining it with lidocaine, as in the Perrotti trial, makes the first applications more comfortable.

At the low strengths used on the anus, the blood pressure effects that these drugs have as tablets are rarely a problem. Still, tell your doctor about every medicine you take. Our guide to Side effects of anal fissure creams and how to manage them covers what is expected and what is a reason to stop.

How do the three ointments compare side by side?

Which one should you start with?

In our practice, and in most colorectal units today, the default is a calcium channel blocker: nifedipine or diltiazem. Nitroglycerin stays a valid option, and your situation can push the choice one way or the other:

• You take erectile dysfunction pills, have low blood pressure or get migraines: choose a calcium channel blocker. Nitroglycerin is a poor fit.
• Pain at each bowel movement is your main problem: nifedipine combined with lidocaine treats the spasm and numbs the area in one application. This is the combination tested in the Perrotti trial. Why lidocaine alone is not enough is explained in Lidocaine cream for anal fissure: why it eases the pain but does not close the tear.
• Your insurance or health system only covers licensed products: in the US and the UK that may make nitroglycerin (Rectiv or Rectogesic) the practical first option. If it gives you headaches you cannot manage, ask to switch rather than stop.
• You are pregnant or breastfeeding: the decision is different and should be made with your doctor; see Which anal fissure cream is safe in pregnancy and while breastfeeding?.
• You have a heart condition or take several blood pressure drugs: any of the three can be used with care, but your doctor needs the full list of medicines first.

If your fissure is recent (under 6 to 8 weeks) and pain is mild, you may not need any of them yet: soft stools and sitz baths close many acute fissures. Our main guide on Which anal fissure cream actually works? A surgeon’s guide by fissure type walks through that first step.

Can you switch to another ointment if the first one fails?

It depends on why it failed.

• You stopped because of side effects (typically the nitroglycerin headache): switching to nifedipine or diltiazem is reasonable and often works, because the fissure never had a full course.
• You used it irregularly or stopped at week 3 when the pain eased: the problem is the course, not the molecule. Restart properly before blaming the drug; Four weeks on fissure cream and no better: what to check and what comes next lists what to check.
• You used it correctly for 6 to 8 weeks with soft stools and the fissure is still open: another ointment is unlikely to change the result. This is the moment for the next step with a colorectal surgeon: a botulinum toxin injection or a lateral internal sphincterotomy. See All guides and All guides.

Whatever ointment you use, some findings mean the problem may be more than a simple fissure. See a doctor without delay if you notice:

What can you actually get in the US, UK, Australia and India?

Availability often decides more than evidence:

• United States: Rectiv (nitroglycerin 0.4 %) is the licensed product. Diltiazem and nifedipine ointments are prepared by compounding pharmacies on prescription; cost and insurance coverage vary widely, so ask before you fill.
• United Kingdom: Rectogesic is licensed and prescribed by many GPs. Diltiazem 2 % is widely used by NHS colorectal teams, usually supplied as an unlicensed "special".
• Australia: Rectogesic is available; diltiazem and nifedipine are usually compounded.
• India: ready-made diltiazem and nitroglycerin ointments are common in pharmacies, which makes a calcium channel blocker easy to start.

How compounded ointments work, and why one prepared in one country cannot be mailed to another, is covered in Compounded fissure cream: what it is, how to get one and why it doesn’t travel. If Rectogesic is the product you were offered, Rectogesic or an alternative? What surgeons weigh before choosing your fissure ointment compares it in detail.

Where does FISURIN fit?

FISURIN belongs to the calcium channel blocker side of this comparison. It is the cream our surgeons at Clínica Proctológica de Lima prescribe for chronic and post-operative fissures: nifedipine plus lidocaine in a water-based hydrogel, with a written 6-week protocol, the same combination studied in the Perrotti trial. It avoids the nitroglycerin headache, but it does not replace soft stools or the full course, and it cannot promise closure in every case. Today FISURIN is a magistral formula prepared under prescription in Peru and is not shipped abroad; FISURIN Hydrogel and FISURIN Relief are in preparation, with a waiting list by country. See what is inside FISURIN or how to get it where you live.