Bentyl

Generic and Brand Names

Bentyl is the brand name for dicyclomine hydrochloride, an anticholinergic agent used to treat irritable bowel syndrome (IBS) and similar conditions involving intestinal muscle spasms.

Available Dosage Forms

Bentyl is available in the following forms:
– Oral tablets: 20 mg
– Oral capsules: 10 mg
– Oral syrup: 10 mg/5 ml
– Injectable solution: 10 mg/2 ml

Pharmacological Category

Dicyclomine hydrochloride belongs to the pharmacological class of antispasmodics and anticholinergics/antimuscarinics.

Indications for Use

Bentyl is indicated for the treatment of patients with functional bowel/irritable bowel syndrome.

Therapeutic Mechanism of Action

Dicyclomine works by relaxing the smooth muscles of the gastrointestinal tract. It blocks the action of acetylcholine at muscarinic receptors, leading to decreased muscle cramps and spasms.

Recommended Dosage Regimen

For adults, the initial dose is usually 20 mg, four times daily. After one week, the dose may be increased to 40 mg four times daily unless side effects limit dosage escalation. Dosage should not exceed 160 mg per day.

Administration Guidelines

Bentyl tablets and capsules should be taken by mouth and can be taken with or without food. The syrup can be measured with a dosing spoon or cup for accuracy. Injectable Bentyl is administered intramuscularly (IM) by a healthcare professional.

Adjustments for Special Populations

Dosage adjustments may be necessary for elderly patients and those with renal or hepatic impairment. Use in these populations should be initiated at a lower dosage due to increased sensitivity to anticholinergics.

Potential Adverse Reactions

Common side effects of Bentyl include dry mouth, dizziness, blurred vision, nausea, and light-headedness. Other potential adverse reactions are constipation, urinary retention, and increased heart rate.

Cautions with Specific Conditions

Bentyl should be used with caution in patients with conditions such as glaucoma, enlarged prostate, myasthenia gravis, and cardiovascular issues due to the anticholinergic effects of the drug.

Drug Interactions of Note

Bentyl may interact with other medications including antihistamines, tricyclic antidepressants, MAO inhibitors, and other anticholinergics, potentially exacerbating side effects or reducing therapeutic efficacy.

Use During Pregnancy and Lactation

Bentyl falls under Pregnancy Category B. Animal studies have not demonstrated a risk to the fetus, but there are no adequate, well-controlled studies in pregnant women. It should only be used when the potential benefits justify the potential risk. Caution should be exercised when administered to a nursing mother.

Overdose Management

Overdose of Bentyl can result in severe anticholinergic effects. Supportive treatment includes activated charcoal, symptomatic and supportive therapy, and potentially, physostigmine as an antidote for life-threatening symptoms.

Storage and Stability

Bentyl should be stored at a controlled room temperature between 68°F to 77°F (20°C to 25°C). The liquid form should not be frozen and should be protected from light.

Instructions for Missed Dose

If a dose is missed, it should be taken as soon as remembered unless it is close to the time of the next dose. In that case, the missed dose should be skipped, and the regular dosing schedule continued. Do not double up on doses to make up for a missed one.

Discontinuation of Treatment

If the decision to discontinue treatment is made, it should be done gradually to mitigate the risk of withdrawal symptoms, which may include worsening of IBS symptoms.