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Dicyclomine: 7 things you should know

Medically reviewed by Carmen Pope, BPharm. Last updated on March 31, 2023.

1. How it works

  • Dicyclomine may be used to treat muscle spasms in the stomach or bowel.
  • Dicyclomine relaxes muscle spasms by directly acting on smooth muscle, and also by indirectly blocking the actions of acetylcholine, a neurotransmitter. Acetylcholine has muscle-activating effects.
  • Dicyclomine belongs to the class of drugs known as anticholinergics. It may also be called an antispasmodic.

2. Upsides

  • Used for the relief of colicky-type pain due to muscle spasms associated with functional bowel/irritable bowel syndrome (IBS). Dicyclomine decreases gastric secretions and the movement of the gastrointestinal tract.
  • Available as a capsule and an oral solution. Also available in an injectable form that may be administered by a healthcare provider.
  • Generic dicyclomine is available.

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Dry mouth, dizziness, blurred vision, inability to sweat, nausea, light-headedness, drowsiness, weakness, and nervousness are the most common side effects.
  • May cause sedation which may affect a person's ability to drive, operate machinery, or perform other hazardous tasks. Alcohol should be avoided because it can enhance this effect.
  • May not be suitable for some people including those with certain gastrointestinal conditions (such as severe ulcerative colitis, reflux esophagitis, an obstruction), glaucoma, myasthenia gravis, liver or kidney disease, heart disease, prostate, or urinary problems.
  • May cause heat exhaustion, particularly in hot climates (dicyclomine decreases the ability to sweat).
  • May cause psychosis in some people; symptoms include confusion, disorientation, short-term memory loss, hallucinations, insomnia, and agitation. Symptoms usually resolve within 12-24 hours of drug discontinuation.
  • May cause breathing difficulties or other serious effects (such as seizures or pulse fluctuations) in infants. Do not use in children less than six months old.
  • May interact with several other drugs including antacids, antiglaucoma agents, other anticholinergics, and drugs that also affect gastric motility (such as metoclopramide), and it may affect the absorption of other drugs because of its effects on gastric motility.

Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects

4. Bottom Line

  • Dicyclomine is used for the relief of colicky pain caused by intestinal muscle spasms in functional bowel/irritable bowel syndrome. Side effects include dry mouth, a decreased ability to sweat, nausea, and sedation.

5. Tips

  • Side effects are usually transient and eventually resolve although some people may require dosage reduction. 9% of people discontinue dicyclomine because of side effects.
  • May cause drowsiness or blurred vision and affect your ability to drive or operate machinery. Avoid alcohol.
  • Dicyclomine may increase your risk of developing heatstroke in hot weather because it decreases your ability to sweat. If symptoms of heatstroke occur (symptoms include fever, nausea, and dizziness after sun exposure), discontinue dicyclomine and seek urgent medical attention.
  • May affect the absorption of other medications. Take other medications at least an hour or two before taking dicyclomine. Talk to your doctor or pharmacist before taking any other medications, including those bought over the counter, to check if they are compatible with dicyclomine.
  • Talk to your doctor if you experience any unexplained diarrhea, severe constipation, hallucinations, loss of muscle control, or other worrisome side effects.

6. Response and effectiveness

  • Peak levels of dicyclomine are reached within 60 to 90 minutes and a reduction in colicky symptoms and muscle spasms should be seen within that time.
  • Effects are relatively short-lived which means dicyclomine needs to be taken up to four times daily.

7. Interactions

Medicines that interact with dicyclomine may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with dicyclomine. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with dicyclomine include:

  • antacids
  • antihistamines such as diphenhydramine or doxylamine
  • botulinum toxin
  • glucagon
  • medications that cause sedation, such as benzodiazepines, muscle relaxants, some seizure medications
  • nitroglycerin
  • opioids, such as oxycodone or morphine
  • other medications that have anticholinergic properties
  • some medications used to treat mental illness, such as clozapine and chlorpromazine
  • tiotropium and ipratropium
  • thiazide diuretics.

Alcohol may enhance the sedative properties of dicyclomine.

Note that this list is not all-inclusive and includes only common medications that may interact with dicyclomine. You should refer to the prescribing information for dicyclomine for a complete list of interactions.


Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use dicyclomine only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2023 Revision date: March 30, 2023.