Hyoscine Butylbromide

What hyoscine butylbromide does

Pain that arrives in waves across the belly usually comes from the muscle in the gut wall squeezing too hard. That is what happens in IBS (irritable bowel syndrome, a long-term condition that causes cramps, bloating and changes in bowel habits), in stomach bugs, and often around periods. Hyoscine butylbromide is an antispasmodic, which means it relaxes that muscle so the spasm lets go and the pain settles. Buscopan is the brand name it is best known by. The same ingredient is used for spasms in other smooth-muscle organs, such as the bladder and the bile ducts, which is why it turns up in more than one kind of cramping pain.

How it works

During a spasm, nerve endings in the gut wall keep releasing a messenger chemical that tells the muscle to tighten. Hyoscine butylbromide occupies the muscarinic receptors that receive it, so the message goes unheard and the muscle relaxes. Because it stays largely in the gut and other smooth muscle, most people do not feel sleepy on it. In IBS it takes the cramp out of a flare-up, but it does not treat the cause of the condition; diet and lifestyle changes do the longer-term work.

Taking Buscopan 10mg tablets

Each tablet is 10mg of hyoscine butylbromide, sugar-coated and small enough to swallow with a glass of water. Take one when a spasm starts and repeat during the day if the pain comes back. Meals make no difference.

Side effects and interactions

A dry mouth is the effect people notice most, and blurred vision, dizziness, constipation, a faster heartbeat, difficulty passing urine and sweating less than usual can also occur. A rash, swelling of the face or throat, or trouble breathing needs urgent help — that is a rare allergic reaction. Other medicines with anticholinergic effects, such as some older antidepressants, antihistamines and bladder medicines, add to the dry mouth and blurred vision, and medicines that speed the gut along (metoclopramide, domperidone) pull against what Buscopan does. It is not suitable for someone with narrow-angle glaucoma (raised pressure inside the eye), myasthenia gravis (a muscle-weakening condition), a blocked bowel or a prostate problem that makes urinating hard.

The Buscopan listing here

Buscopan 10mg tablets are the one hyoscine butylbromide product, in the digestive health category with other medicines for the gut. Its product page shows the pack sizes and the current price. To compare it with something else, match the ingredient and the strength, 10mg of hyoscine butylbromide per tablet, rather than the name on the box.