What You Need To Know About Bentyl (Dicyclomine)

Prescribing, Dosing, Side Effects, and Use During Pregnancy and Nursing

Bentyl (dicyclomine) is a type of drug known as an anticholinergic. It is also an antispasmodic that prevents spasms in the muscles of the gut and bladder by causing those muscles to relax. This drug also reduces the amount of acid that is produced in the stomach.

  • Bentyl is an antispasmodic drug
  • Bentyl is sometimes prescribed to treat irritable bowel syndrome (IBS)
  • Only the prescribed amount of Bentyl should be taken
  • Taking antacids at the same time as Bentyl can reduce its effectiveness
  • People taking Bentyl should not drink
  • Constipation can be a side effect of Bentyl
  • Breastfeeding mothers should not take Bentyl

How Bentyl Is Taken

Bentyl comes in the form of a capsule, a tablet, an oral liquid, and an intramuscular injection. It is usually taken four times per day. The injection is used only temporarily for one or two days. To achieve the best results, Bentyl should be taken 30 minutes to one hour before eating a meal.

Bentyl should not be taken at the same time as an antacids, such as Tums, Rolaids, Gaviscon, Maalox, and Mylanta, as they may reduce the effectiveness of Bentyl.

The dosage of Bentyl needed will be determined by the prescribing physician. Take this medication exactly as prescribed. In some cases, the starting dose might be 20 mg four times a day. After this dosage is taken and tolerated for a week, the dose might be increased to 40 mg four times a day.

Why Bentyl Is Prescribed

Bentyl may be prescribed to treat conditions such as IBS, diverticulosis, colic, and bladder spasms.

What To Do If A Dose Is Missed

If a dose is missed, take it as soon as it is remembered. If the next dose should be taken soon, just take that dose. Don't double up, or take more than one dose at a time.

Who Should Not Take Bentyl

Tell a doctor if any of the following conditions are present now or have been diagnosed in the past:

  • Congestive heart failure
  • Difficulty urinating
  • Esophagitis
  • Glaucoma
  • Hypertension (high blood pressure)
  • Myasthenia gravis
  • Prostate enlargement (BPH)
  • Severe ulcerative colitis when bowel movements have stopped

Bentyl Side Effects

Serious side effects of Bentyl include mental changes such as confusion, short-term memory loss, hallucinations, or agitation. In most cases, these side effects will go away during the 12 to 24 hours after the patient stops taking Bentyl.

Some of the more common side effects include dry mouth, drowsiness, and dizziness. Bentyl could also lead to a decreased ability to perspire (which can contribute to heat stroke). 

It is important to drink enough water while taking Bentyl, especially during hot weather or while exercising.

Sexual Side Effects

Bentyl has caused impotence in some men who take it.

Medication Interactions

Bentyl may interact with the certain other medications. Tell the prescribing physician if any of these medications are also prescribed:

  • Symmetrel (amantadine)
  • Antacids
  • Antidepressants (Haldol, Elavil)
  • Antihistamines (Benadryl)
  • Cardiac rhythm regulators (Pronestyl, quinidine)
  • Tagamet (cimetidine)
  • Lanoxin (Digoxin)
  • Reglan (Metoclopramide)
  • Monoamine oxidase (MAO) inhibitors (Nardil, Parnate)
  • Prednisone
  • Sedatives (Ambien, Dalmane, Restoril)
  • Thiazide diuretics (Dyazide, hydrochlorothiazide)

Food Interactions

Bentyl is not known to interact with any foods. People taking Bentyl should avoid alcoholic drinks as the two together could have an increased sedative effect. Take care to avoid alcohol from unexpected sources, such as over-the-counter cough suppressants or products to treat colds (Nyquil, for example). Bentyl can cause constipation, and patients should get enough fiber and drink enough water to counteract this effect.

Safety During Pregnancy

The FDA has classified Bentyl as a type B drug. The effect that Bentyl has on an unborn child has not been studied extensively. Bentyl should only be used during pregnancy if clearly needed. Notify the prescribing doctor if you become pregnant while taking Bentyl.

Bentyl should not be taken by women who are breastfeeding a baby as Bentyl passes into breast milk and could affect a nursing infant. 

Bentyl should not be taken by women who are breastfeeding a baby as Bentyl passes into breast milk and could affect a nursing infant.

Children under 6 months of age may experience severe side effects from this drug. Bentyl can suppress the production of breast milk in nursing mothers.

How Long Bentyl Can Be Taken Safely

Under the supervision of a physician, Bentyl can safely be used long term.

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Article Sources

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  2. Trinkley KE, Nahata MC. Medication management of irritable bowel syndrome. Digestion. 2014;89(4):253-67. doi:10.1159/000362405

  3. Kaiser Permanente. Dicyclomine 10 mg/5 mL oral solution. Updated November 2019.