What side effects do anal fissure creams cause?
Fissure creams fall into two groups, and their side effects follow the same split. Sphincter relaxants (nitroglycerin, nifedipine, diltiazem) act on smooth muscle and blood vessels, so a small part of the dose can reach the rest of the body and cause headache, flushing or dizziness. Symptom creams (lidocaine, steroids, hemorrhoid creams) act on the skin, so their problems are local: irritation, allergy, thinning.
The good news is that almost all of these effects are mild, dose-related and reversible. The bad news is that they are a leading reason people abandon treatment before the 6 to 8 weeks a chronic fissure needs. Knowing what to expect, and what to do about it, is part of the treatment. The Cochrane review of non-surgical therapy concluded that calcium channel blockers and botulinum toxin match nitroglycerin’s efficacy with fewer adverse effects, which is why most colorectal surgeons now start with nifedipine or diltiazem.
Why does nitroglycerin ointment cause headaches, and what helps?
Nitroglycerin releases nitric oxide, which relaxes the internal sphincter but also widens blood vessels in the head. The result is a throbbing headache, usually starting soon after the application and easing within an hour or two. It affects up to half of patients, sometimes with lightheadedness when standing up. Products include Rectogesic (UK, Australia, Europe) and Rectiv (US).
What helps, in practice:
- Use the prescribed amount and no more. Extra ointment means extra headache without extra healing.
- Wear a finger cot or glove so you do not absorb a second dose through your fingertip.
- Apply it sitting or lying down, and get up slowly afterward.
- Ask your doctor about a simple pain reliever such as acetaminophen for the first days; the headache often fades as the body adapts.
One rule is absolute: do not combine nitroglycerin with erectile dysfunction drugs such as sildenafil, tadalafil or vardenafil. Together they can drop blood pressure dangerously. Tell your doctor about any heart or blood pressure medication too.
If the headache makes you skip doses, switch rather than suffer. A systematic review of seven randomized trials (481 patients) found diltiazem as effective as nitroglycerin, with fewer headaches (risk ratio 0.39) and fewer recurrences (Sajid, 2013). More in Nitroglycerin ointment for anal fissure: does it work, and can you live with the headache? and Rectogesic or an alternative? What surgeons weigh before choosing your fissure ointment.
What are the side effects of nifedipine and diltiazem creams?
Topical nifedipine and diltiazem are calcium channel blockers, the same family used in tablets for blood pressure, but applied in small amounts to the anal canal. The most frequent complaints are local:
- Burning or stinging for a few minutes after application, more noticeable in the first days when the fissure is raw.
- Itching around the anus, especially with diltiazem or when too much cream is left on the outer skin.
Effects elsewhere in the body are uncommon at topical doses: facial flushing, mild dizziness or headache, usually milder than with nitroglycerin. If you already take a calcium channel blocker or other blood pressure tablets, tell the prescriber, and stand up slowly if you feel lightheaded.
Many compounded nifedipine ointments include lidocaine, which eases the sting of application. That is the combination tested in a randomized double-blind trial of nifedipine 0.3 % with lidocaine 1.5 % used for 6 weeks (Perrotti, 2002). In the US, UK, Australia and India these ointments are usually compounded, so the base varies: if burning persists, ask whether a different base is possible. Details in Nifedipine cream for anal fissure: dose, application, side effects and the 8-week plan and Diltiazem 2% cream for anal fissure: who it is for, how to use it and what to expect.
Can lidocaine or steroid creams cause problems?
Lidocaine is useful before bowel movements, but it is not harmless when used many times a day for weeks. Possible problems:
- Local irritation and redness.
- Contact allergy, which shows up as itching and a rash that gets worse, not better, with each application.
- Numbness that hides how the fissure is really doing.
Use the smallest amount that makes the bowel movement bearable, and see Lidocaine cream for anal fissure: why it eases the pain but does not close the tear for how to combine it with a relaxant.
Steroid creams (hydrocortisone and many hemorrhoid creams that contain one) calm itching and inflammation, but corticosteroids thin the anal skin and can slow healing of the tear. Prolonged use also favors fungal infection. The rule we repeat in every consultation: never use hydrocortisone for more than 7 days unless a doctor tells you otherwise. Our guide on Hydrocortisone cream for an anal fissure: when it helps and why never more than 7 days covers when a short course makes sense.
Is the burning from the cream, the fissure or an allergy?
It helps to separate three situations, because each has a different answer:
| What you feel | Likely cause | What to do |
|---|---|---|
| Stinging for a few minutes after each application, fading over the first week | Cream on a raw fissure | Keep going; use a smaller amount, apply after a sitz bath |
| Sharp pain during and for hours after the bowel movement | The fissure itself and the sphincter spasm | Keep the cream, soften stools, add a sitz bath |
| Itching and a red rash that spreads and worsens day by day | Irritation or contact allergy | Stop the cream and see your doctor; do not cover it with a steroid on your own |
| Swelling of lips or face, hives, trouble breathing | Generalized allergic reaction (rare) | Emergency care |
Moisture also matters. A thick layer of cream plus sweat can macerate the skin and cause itching that people mistake for the fissure getting worse. Pat dry, wear cotton underwear and keep the amount to a pea-sized dose. If itching is your main symptom, read Why does an anal fissure itch, and how do you calm it?.
Can fissure creams weaken the sphincter or cause incontinence?
This is a common fear, and the answer is reassuring. Topical sphincter relaxants lower the resting pressure of the internal sphincter only for the hours after each application; the effect wears off and the muscle returns to its normal tone when you stop. They do not cut or damage the muscle. In the randomized trial that compared botulinum toxin with nitroglycerin ointment, no patient in either group developed fecal incontinence (Brisinda, 1999).
A few people notice slight difficulty holding gas in the first days, which settles. If you have true leakage of stool, tell your doctor: it is not an expected effect of the cream and deserves an examination. Permanent changes to the sphincter are a question for surgery, not for ointments; see All guides.
If you are pregnant or breastfeeding, the choice of cream changes; read Which anal fissure cream is safe in pregnancy and while breastfeeding? before starting any of them.
When is a side effect a reason to stop and see a doctor?
Most side effects can be handled by adjusting the dose or switching cream. Stop and seek care without delay if you have:
- Fainting, chest pain, palpitations or severe dizziness after applying the cream.
- A headache that is the worst of your life or comes with weakness, confusion or vision changes.
- Swelling of the face or lips, hives or difficulty breathing.
- A spreading rash, fever, pus or a painful swelling next to the anus.
- Bleeding after the age of 45, blood mixed with the stool, a lump that grows or weight loss.
If side effects have kept you from using any cream correctly for 6 to 8 weeks, botulinum toxin or a lateral internal sphincterotomy may be the better route. See Four weeks on fissure cream and no better: what to check and what comes next and our surgery page.
Where does FISURIN fit?
FISURIN combines nifedipine, a sphincter relaxant that avoids most of the headaches of nitroglycerin, with lidocaine to ease the sting of application, in a water-based hydrogel prescribed by our surgeons at Clínica Proctológica de Lima. It can still cause local burning or itching, it is not free of side effects, and it does not suit everyone, which is why it is used under prescription with a review at the end of the 6-week protocol. Today it is a magistral formula prepared in Peru and is not shipped abroad; FISURIN Hydrogel and FISURIN Relief are in preparation, with a waiting list. See what is inside FISURIN or how to get it where you live.
Frequently asked questions
What are the side effects of nifedipine cream for fissure?
Mostly local burning or itching after application. Flushing, mild dizziness or headache are uncommon and usually milder than with nitroglycerin.
How common are headaches with nitroglycerin ointment?
They affect up to half of patients. Using the exact dose, wearing a finger cot and applying it lying down help; if they persist, nifedipine or diltiazem are alternatives with fewer headaches.
Does diltiazem cream cause headaches?
Less often than nitroglycerin. A systematic review of seven randomized trials found fewer headaches with diltiazem (risk ratio 0.39) and similar healing.
Can fissure cream cause incontinence?
Topical relaxants act for hours and wear off; they do not damage the sphincter. In a randomized trial of nitroglycerin ointment versus botulinum toxin, no patient developed fecal incontinence.
Is it safe to use hydrocortisone cream on a fissure for weeks?
No. Steroids thin the anal skin and can slow healing. Never use hydrocortisone for more than 7 days without medical advice.
Can I use nitroglycerin ointment if I take Viagra or Cialis?
No. Nitroglycerin combined with sildenafil, tadalafil or vardenafil can cause a dangerous fall in blood pressure. Tell your doctor, who can prescribe nifedipine or diltiazem instead.