BMA Concise Guide to Medicine & Drugs

Dicycloverine (Dicyclomine)

Brand name Merbentyl

Used in the following combined preparation Kolanticon


Drug group Drug for irritable bowel syndrome

Overdose danger rating Medium

Dependence rating Low

Prescription needed No (doses of 10mg or less); Yes (doses of more than 10mg)

Available as generic No


Dicycloverine is a mild anticholinergic drug that relieves painful abdominal cramps caused by spasms of the smooth muscle in the wall of the gastrointestinal tract. It can be used to treat irritable bowel syndrome, and colicky conditions in babies (only over 6 months).

Because the drug has anticholinergic properties, it is also included in some combined preparations used to treat flatulence, indigestion, and diarrhoea. Dicycloverine relieves symptoms but does not cure the underlying condition. Additional treatment with other drugs and self-help measures, such as dietary changes, may be recommended by your doctor.

Side effects with dicycloverine are rare, but they include headaches, constipation, urinary difficulties, and palpitations.


Follow instructions on the label. Call your doctor if symptoms worsen.

How taken/used Tablets, liquid.

Frequency and timing of doses 3–4 x daily before or after meals.

Dosage range Adults 30–60mg daily. Children Reduced dose according to age and weight.

Onset of effect Within 1–2 hours.

Duration of action 4–6 hours.

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children. Protect from light.

Missed dose Take as soon as you remember. If your next dose is due within 2 hours, take a single dose now and skip the next.

Stopping the drug The drug can be stopped without causing problems when it is no longer needed.

Exceeding the dose An occasional unintentional extra dose is unlikely to cause problems. Large overdoses may cause drowsiness, dizziness, and difficulty in swallowing. Notify your doctor.


Most people do not notice any adverse effects when taking dicycloverine. Those that do occur are related to its anticholinergic properties and include drowsiness, dry mouth, constipation, headache, and blurred vision. Such symptoms may be reduced by adjusting the dosage, or they may disappear after a few days as your body adjusts to the drug. If you experience difficulty in passing urine or palpitations, consult your doctor.


Sedatives All drugs that have a sedative effect on the central nervous system may increase the sedative properties of dicycloverine.

Anticholinergic drugs These drugs may increase the adverse effects of dicycloverine.


Be sure to tell your doctor if:

· You have glaucoma.

· You have urinary problems and/or an enlarged prostate gland.

· You have a hiatus hernia or suffer from heartburn or acid reflux.

· You have any heart condition.

· You have myasthenia gravis

· You are taking other medicines.

Pregnancy No evidence of risk.

Breast-feeding The drug passes into the breast milk, but at normal doses adverse effects on the baby are unlikely. Discuss with your doctor.

Infants and children Reduced dose necessary. Not recommended in infants under 6 months.

Over 60 Reduced dose may be necessary. The elderly are more susceptible to anticholinergic side effects.

Driving and hazardous work Avoid such activities until you have learned how dicycloverine affects you; the drug can cause drowsiness and blurred vision.

Alcohol Caution. Alcohol may increase the sedative effects of this drug.


No problems expected.