What You Need to Know About Bentyl (Dicyclomine)

Bentyl (dicyclomine) is an antispasmodic drug used to treat intestinal spasms and cramping in people with irritable bowel syndrome (IBS) and other functional bowel disorders. Dicyclomine can be used both in adults and children and is available as a tablet, capsule, syrup, or injection. (Only the injection is still used under the trade name Bentyl.)

Bentyl can cause side effects and interact with certain drugs, but the benefits may outweigh the risks when faced with severe IBS symptoms.

This article describes the uses, dosage, risks, side effects, and interactions associated with taking Bentyl.

Uses of Bentyl

Bentyl belongs to a class of drugs known as anticholinergics that block the action of a chemical known as acetylcholine. Acetylcholine is used by the body to contract smooth (involuntary) muscles in the airways, bladder, blood vessels, gastrointestinal (digestive) tract, and others of the body.

By doing so, drugs like Bentyl can relieve spasms in the gut and intestines.

Bentyl is approved for use by the U.S. Food and Drug Administration (FDA) in treating IBS and other functional bowel disorders. These are conditions of unknown origin affecting the middle and lower intestines that cause a cascade of chronic (persistent) symptoms, including abdominal pain, bloating, indigestion, stool irregularity, diarrhea, and constipation.

Irritable bowel syndrome is the most common type of functional bowel disorder. 

Before Taking Bentyl

Tell your healthcare provider about all medications, supplements, and vitamins you take before starting Bentyl. While some drugs pose minimal risks, others can cause severe interactions and/or side effects when used together.

Precautions and Contraindications

Because anticholinergic drugs affect smooth muscles throughout the body, they can affect the normal contraction of other organs and may be inappropriate for people with certain health conditions.

Tell your healthcare provider if you have any of the following:

• Bladder outlet obstruction
• Bowel obstruction
• Chronic kidney disease
• Congestive heart failure
• Coronary artery disease
• Diabetic neuropathy
• Enlarged prostate
• Gastroesophageal reflux disease (GERD)
• Glaucoma
• High blood pressure
  
• Myasthenia gravis
• Tachycardia (irregular heartbeats)
• Ulcerative colitis

Dicyclomine is a pregnancy category B drug, meaning that no harm was reported in animal studies but studies in humans are lacking. Dicyclomine should only be used during pregnancy if the benefits outweigh the risks. Notify your healthcare provider if you become pregnant while taking dicyclomine.

Bentyl should not be taken while breastfeeding as the drug can be passed into breast milk.

Bentyl Dosage

Bentyl can be taken by mouth as a tablet, capsule, or syrup. It is also formulated as an intramuscular injection (meaning a shot into a large muscle) for temporary use in those who can't take oral medication.

The Bentyl dose is measured in milligrams (mg). A typical starting dose of the oral forms is 80 mg/day, divided equally into four doses. If that is tolerated but not effective, the dosage may be increased to 160 mg/day.

The injection is given in doses of 10 mg or 20 mg four times per day.

If a dose is missed, take it as soon as you remember. If the next dose is soon, skip the missed dose and continue as normal. Never double up doses as it can increase the risk or severity of side effects.

Bentyl Side Effects

As with all drugs, Bentyl can cause side effects ranging from mild to severe. Some people have no side effects at all.

Common side effects of Bentyl include:

• Dry mouth
• Dizziness or light-headedness
• Blurred vision
• Nausea
• Drowsiness
• Weakness
• Nervousness or agitation
• Stuffy nose
  
• Headache
• Abdominal bloating
• Constipation
• Insomnia

Call your health provider immediately if the side effects are severe or you experience any of the following uncommon side effects:

• Rash
• Hot, dry skin
• Difficulty breathing
• Difficulty swallowing
• Vomiting
  
• Rapid or irregular heartbeats
• Mood changes
• Delirium
• Hallucinations
• Fainting
• Unsteadiness
• Weakness
  

Warnings and Interactions

Bentyl can interact with other drugs with similar anticholinergic effects. There are also certain drugs that can either lower or increase the concentration of Bentyl in the blood.

Tell your healthcare provider if you take any of the following before starting Bentyl:

• Antacids
• Antiarrhythmic drugs like Pacerone (amiodarone)
• Antidepressants, including tricyclic antidepressants and monoamine oxidase inhibitors (MAOIs)
• Antipsychotics like Compazine (prochlorperazine)
• Benzodiazepines like Valium (diazepam)
• Corticosteroids (steroids) like prednisone
• Glaucoma medications like Vyzulta (latanoprostene)
• Gocovri (amantadine)

People taking Bentyl should also avoid alcohol as it can increase the drug’s sedative effects.