Clozapine’s Fatal Constipation – Free Page

Clozapine – The Best Medication for Schizophrenia

Schizophrenia is easier than ever to treat because there are so many effective medications from which to choose. But there’s one unique old medication that’s considered to be the best: clozapine. If you’re one of our paid subscribers, we have a whole article describing that it’s the best. Especially for people whose schizophrenia has not been helped by one or two other medications, clozapine has been found to be the best next medicine to try. The medical literature has many reviews offering this opinion and doctors who treat schizophrenia pretty much agree. When someone with schizophrenia can’t find any other medicine that works, try clozapine. The reason it’s not the first “go-to” medicine is that it has one rare but potentially fatal side effect. It might lower a person’s white blood cell count leaving them at risk for serious illness or death from infection.

an old antique tin that originally contained glycerine suppositories - photo by bluebudgie
antique glycerin suppository tin – photo by bluebudgie

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Clozapine’s Fatal Constipation – Another Known Risk

This terrible constipation clozapine side effect is more manageable than the low white cell count adverse reaction, but only if you are aware that it can happen and that it can be serious. So, whether you’re the doctor prescribing clozapine, or a person taking it, or if you know a person who takes it, you need to know about clozapine and the possibility of fatal constipation. If someone taking clozapine starts to get constipated it has to be very actively treated. The individual has to pay attention to it. In January 2020 the FDA strengthened the warning about untreated constipation in people taking clozapine because it can cause such serious, or even fatal, bowel problems. The higher the dose of clozapine taken, the higher the risk for this side effect. The risk is also increased if other medicines that cause constipation are used along with the clozapine.

The Bowel Problems That Can Lead to Hospitalization and Death

Common with clozapine are bowel side effects. If these side effects are not treated they can lead to complications that are at least super uncomfortable. It the constipation progresses it can require medical care or even require hospitalization. So if someone taking clozapine gets constipated, it has to be treated. It’s always been known that clozapine changes how the bowels work. While death from clozapine’s bowel side effects is not common, it can happen. If bowel problems on clozapine are not treated quickly, serious bowel complications can develop, like complete bowel blockage. It is in these situations that deaths have been known to happen.

What You Should Do If You’re Taking Clozapine

If you’re taking clozapine and having trouble with constipation, you have to talk to your doctor about it. Tell your doctor how moderate or bad the constipation is and all the other medicines you’re taking, including over-the-counter medicine and health supplements. Constipation means less than your usual number of bowel movements. It’s most important for you to talk with your doctor if you have less than 3 bowel movements a week, you have dry stools or hard stools, or you can’t pass gas. The common symptom with clozapine-induced constipation is severe diffuse abdominal pain. It’s even more serious if you also have nausea, bloating or belly swelling, belly pain, and/or vomiting.

How To Avoid Constipation If You’re Taking Clozapine

There are things you can do to try to prevent getting constipated on clozapine. The foods you eat are important. Try to eat more vegetables, grains, and fruits, that is, go with a high fiber diet. But, unless your doctor tells you otherwise, avoid “bulking” supplements like Metamucil or other psyllium products, and avoid fiber supplements. Make sure to drink plenty of liquids including lots of water. And start a regular exercise program. Exercise helps the bowels work better. It might be good to take a laxative, too, even before your constipation gets bad. Ask your doctor which ones are recommended.

Other Medicines That Slow the Bowels, So Don’t Take With Clozapine

(But First Ask Your Doctor)

  • Calcium supplements
  • Medicines for acid stomach that have calcium and/or aluminum in them
  • Antihistamines used for allergies and colds
  • Medicines like ibuprofen that are used for pain
  • Muscle relaxants
  • Opioids (narcotics) used for pain, like codeine and morphine
  • Medicines for psychosis other than clozapine
  • Medicines for depression, especially the “tricyclic antidepressants”
  • Medicines for calming the stomach and for nausea
  • Iron supplements
  • Some medicines for epilepsy like phenytoin and clonazepam
  • The heart rhythm and high blood pressure medicines called calcium channel blockers. For example, verapamil
  • Some Parkinson’s disease medicines
  • Medicines for urine incontinence

The New FDA Warnings Are Based on a Big FDA Review

You might wonder, why the big deal now on this topic. The red flag went up because the FDA reviewed reports dating from 2006 to 2016. During this time they found 10 cases of constipation that became serious. The serious bowel problems led to hospitalization, surgery, or death. In one case the walls of the large bowel actually just died. In another the blood supply to the bowel had completely stopped. Yet another case described that the bowel itself died, and still another had abdominal swelling that led to bowel obstruction. Some of these cases were reported to the FDA directly and others the FDA found in the medical literature. The FDA realized that there are likely many more cases that were never reported.

Example: Small Bowel Holes from Clozapine

There’s a case report from Portugal about holes that developed in the small intestine from clozapine. The individual was taking clozapine 600 mg daily. He went to the hospital Emergency Department with belly pain. The situation required an emergency abdominal surgery. At surgery the doctors saw multiple small holes in different parts of his small bowel. They had to take out 5 feet (1.5 meters) of his small bowel and part of his large bowel to save his life. He was in the hospital 28 days. He did survive and was able to go home.

Example: Death Due To Clozapine Constipation

An article in Psychosomatics describes a case report of a less fortunate individual who died as a result of clozapine constipation that got so bad it blocked his entire colon. The guy was 43 years old and had several medical problems. He was taking clozapine 750 mg a day for 6 years. He came to the hospital confused, vomiting, and blue, with a fast heart rate, fast breathing, and blood pressure so low that it could not be measured. He had a hard, inflamed belly. At surgery the surgeons found complete bowel blockage due to hard constipation. His colon was removed and he was put in ICU with maximal care. Despite this continuous close medical supervision and maximum care in the ICU he died 3 weeks later of a massive infection and the failure of several organs.

an old one-person outhouse/water closet fancy elaborate funny - photo by Domainick
funny fancy old outhouse water closet – photo by Domainick

The FDA Does Not Want You to Avoid Clozapine – Just Be Aware and Careful of Constipation

One of the FDA’s central jobs it to warn everyone, doctors, patients, and the family and friends of patients, about any risks of medication. This FDA warning about clozapine’s fatal constipation does not mean that anyone should just stop clozapine without a discussion with their doctor. The FDA’s warning is meant to make you aware that if you’re taking clozapine and you get constipated, don’t treat it as a minor problem. Constipation when taking clozapine is an important medical condition that needs treatment, so discuss it with your doctor. Your doctor will instruct you on how to treat any mild constipation so that it never gets worse. And if the constipation does not get better no matter what you do, your doctor will help you find a different medication to take instead of clozapine.

Helpful Links:

FDA Strengthens Clozapine Warning

The journal Cureus on Clozapine-induced Constipation

Dr. Ananya Mandel’s list of drugs that cause constipation

International Journal of Surgery Case Report on Bowel Perforations due to Clozapine

Clinical Psychiatry News – Clozapine-induced GI hypomotility: From constipation to bowel obstruction

Psychosomatics article on Death From Clozapine-Induced Constipation

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