Colofac (mebeverine hydrochloride) is a prescription antispasmodic medication indicated for the treatment of symptoms associated with irritable bowel syndrome (IBS) 1. This medication alleviates IBS symptoms by relaxing the muscles within the intestine. Colofac is administered orally (tablet, capsule or liquid) and should be taken as prescribed by your doctor. Before you begin treatment with this medication, discuss possible side effects with your doctor.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.

Digestive Upset

You may develop stomach upset as a side effect of taking Colofac. You may experience painful or burning sensations within your chest or throat--a condition referred to as heartburn or indigestion. Treatment with Colofac can also affect your ability to have a normal bowel movement. Certain patients experience constipation, a condition that makes it difficult to pass a stool. Such symptoms can contribute to a significant decrease in your normal appetite.

Skin Rash

Treatment with Colofac can cause a skin rash to develop in certain patients. You may notice that patches of your skin appear red, irritated or inflamed. The skin rash may also be itchy or dry.


You may experience abnormal sensations of dizziness or lightheadedness while taking Colofac. Episodes of dizziness can have a negative impact on your ability to walk or drive normally. If you experience dizziness or lightheadedness after taking a dose of Colofac, sit down until the sensation passes to prevent further injury from falling.

Sleeping Difficulties

Sleeping difficulties can occur during treatment with Colofac, explain health professionals at the Better Health Channel, an informational health website provided by the Australian government. During treatment, you may find it difficult to fall asleep or stay asleep (insomnia). Such side effects can contribute to additional symptoms of excessive daytime tiredness or fatigue.


Colofac treatment can cause headache to occur in certain people. Headache symptoms are typically mild to moderate in severity and may be accompanied by other side effects, such as dizziness or fatigue.

Decreased Heart Rate

While receiving treatment with Colofac, you can develop abnormal changes to your heart rate. Certain people may experience a decreased heart rate, which can contribute to side effects of dizziness, fatigue and headache. Speak with your doctor immediately if you notice any heart-related changes while taking Colofac.