Healthy Living

What Do Antispasmodic Medicines Do?

Antispasmodic medicines have been proven to moderately and effectively relieve gastrointestinal symptoms.

What Do Antispasmodic Medicines Do?

Antispasmodic medicines are commonly prescribed drugs for irritable bowel syndrome (IBS). These medications can help relieve abdominal cramping and pain, which are common symptoms experienced by people with IBS. However, antispasmodic medications might not be suitable for people who have IBS with constipation (IBS-C) as these drugs tend to have a constipating effect. 

According to the Centers for Disease Control and Prevention (CDC), symptoms of irritable bowel syndrome (IBS) are experienced by approximately 1.3 million Americans. Irritable bowel syndrome (IBS) is a common digestive disorder that causes abdominal pain along with changes in bowel habits.

The treatment of this disorder usually focuses on relieving the symptoms, such as cramping, abdominal pain, bloating, constipation, and diarrhea. Antispasmodics are drugs that have been proven to moderately and effectively relieve these gastrointestinal symptoms. These drugs work by relaxing the smooth muscles of the digestive tract. The symptoms of IBS tend to occur after eating, so antispasmodics are usually taken 30-60 minutes before meals. 

Antispasmodic Medicines for IBS

1. Anticholinergics

Anticholinergics are drugs that are designed to block the action of the chemical compound called acetylcholine. This chemical is produced by the body and acts on the autonomic nervous system. Its role is to transfer signals between cells to affect different functions of the body.

When the receptors of acetylcholine in the digestive system are blocked, overproduction of mucus and severe muscle spasms can be reduced. However, anticholinergics can also affect other organs and trigger side effects, such as dizziness, blurred vision, decreased urine output, and constipation. Another common side effect of anticholinergics is gastric reflux.

Since the use of these drugs may lead to constipation, they are best used in patients with irritable bowel syndrome with diarrhea (IBS-D) than those with irritable bowel syndrome with constipation (IBS-C).

Some antispasmodics and anticholinergics are used along with antacids and other medications for peptic ulcer treatment. Others are taken to prevent symptoms of motion sickness, nausea, and vomiting. 

Antispasmodics and anticholinergics are also used in certain emergency procedures, such as an emergency surgery. Some of these drugs are given before administering anesthesia to help patients relax and to reduce secretions, such as saliva. Hyoscyamine, atropine, scopolamine, and glycopyrrolate may be used during anesthesia and surgery to help normalize a patient’s heartbeat.

Scopolamine can also be used to help prevent nausea and vomiting after giving anesthesia and postsurgery. Atropine injections for specific types of procedures can help relax the stomach and intestines.  

The anticholinergics that are commonly prescribed are:

  • Bentyl (dicyclomine hydrochloride): Bentyl is an anticholinergic and antispasmodic drug available in the form of capsules, tablets, and injections. This medication is used for the treatment of IBS. 
  • Buscopan (hyoscine butylbromide): This medication is available in tablet and injection form. However, injections are only given in hospitals. Buscopan tends to work very quickly with painful cramps easing as fast as 15 minutes from ingestion. Side effects to this drug are unusual, but some users may experience dry mouth, blurred vision, and constipation. 
  • Levsin (hyoscyamine): This drug comes in the form of oral tablets. It is also one of the main antispasmodic and anticholinergic components of belladonna alkaloids. It can be used as adjunctive therapy for the treatment of IBS and functional gastrointestinal disorders.

2. Mebeverine

Mebeverine is a drug that works in the same way with anticholinergics. However, this drug does not cause acetylcholine side effects. Some allergic reactions in the form of low-grade skin rash have been reported with its use.

Mebeverine is available under many brand names, such as Duspatalin, Duspamen, and Colofac, and is commonly prescribed to individuals with IBS. 

Alternative Antispasmodics

Peppermint Oil

Peppermint oil contains menthol, which is a substance that possesses relaxing effects on smooth muscles. It is usually recommended due to its anti-nausea and soothing effects on the colon and gastric mucosa.

According to a review study conducted by gastroenterology specialists at the University of California, San Diego, people who took enteric-coated peppermint oil capsules were more likely to find relief from the symptoms of IBS than those who were provided a placebo.

Although the short-term use of peppermint oil is considered safe, this supplement is also known for causing heartburn. This situation may be avoided by using the enteric-coated capsules. People with heartburn, severe liver damage, bile duct obstruction, gallbladder inflammation, or hiatal hernia must use peppermint oil with caution.

Always consult your healthcare provider before taking peppermint oil or other over-the-counter herbal supplements. 

Antispasmodics for Cerebral Palsy

Antispasmodic and anticholinergic medications are also used to help relieve muscle spasms and uncontrolled body movements that are usually observed in people with cerebral palsy. Other types of medications are also used to help manage pain and other co-occurring disorders.

Uncontrollable body movements include tremors and spasms, muscle stiffness, and drooling that is associated with non-spastic cerebral palsy. When certain anticholinergics are used in large doses, they tend to stimulate the nervous system, but when used in small doses, they act as antidepressants.

Their other common uses include reducing saliva and bronchial secretions, as well as treating spastic conditions in the GI tract. There are also some forms of cerebral palsy, in which anticholinergics may be prescribed. They include:

  • Dystonia: Characterized by involuntary contractions with abnormal posture, tremors, and twisting motions.
  • Chorea: Uncontrollable, irregular, involuntary, and jerky movements
  • Athetosis: Slow, convoluted, involuntary, and often repetitive writhing movements.
  • Choreoathetoid: A combination of athetosis and chorea. 

Anticholinergics prevent the neurotransmitter acetylcholine from binding to nerves, and limit the stimulation of muscles. The side effects of these medications are often mild. However, their side effects may be amplified with antihistamine use.

Other common anticholinergic drugs are:

  • Sinemet (carbidopa-levodopa)
  • Trihexyphenidyl hydrochloride
  • Benztropine mesylate
  • Kemadrin (procyclidine hydrochloride)
  • Robinul (glycopyrrolate)

Aside from anticholinergic drugs, effective treatment for cerebral palsy involves a combination of other medications, surgery, and other intervention methods. However, since cerebral palsy treatment often begins at an early age, doctors and some parents may share the same concerns regarding the side effects of long-term drug therapy. Reliance on medications can be reduced by ensuring a healthy nutrition, physical therapy, and other treatment options. 


Epidemiology of the IBD. (March 2015)

Khanna, R., et. al. Peppermint Oil for the Treatment of Irritable Bowel Syndrome: A Systematic Review and Meta-analysis. Journal of Clinical Gastroenterology. (July 2014)

Medication and Drug Therapy. (n.d.)