What Are Anticholinergic Effects?

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Anticholinergic effects are changes that occur within the body when a substance that counteracts the neurotransmitter acetylcholine is ingested. These effects may be the result of certain medications, as well as plant toxins and pesticides. Acetylcholine is involved in many major bodily functions and therefore anticholinergic effects will be experienced throughout the body.

Due to this effect on acetylcholine, medications that aim to target specific symptoms of an illness or disorder often end up causing other unwanted side effects.

 Some of the time these effects are only temporary and diminish as a person adjusts to the medication. At other times, these side effects can be quite severe and debilitating. Elderly individuals appear to be at higher risk for more significant impairment from anticholinergic side effects.

In some cases, medications are specifically prescribed to take advantage of their anticholinergic effects. An example of this would be the use of antidepressants and antispasmodics in the treatment of irritable bowel syndrome (IBS), particularly in cases where the predominant symptom is diarrhea. The anticholinergic effect of slowing down of the movement of the digestive system is desirable in order to reduce the frequency of diarrhea episodes.

Common Anticholinergic Side Effects

The following are some of the more common side effects that a person may experience when taking a medication that has anticholinergic effects:

  • Blurred vision
  • Constipation
  • Decreased sweating
  • Dizziness
  • Dry mouth
  • Slowing down of urination

Other less common side effects include:

  • Bowel obstruction
  • Cognitive impairment
  • Dilated pupils
  • Increased heart rate

Severe side effects can occur in rare cases. If you are experiencing any side effects that are alarming to you, seek medical attention immediately.

What Medications Are Most Likely to Cause Anticholinergic Side Effects?

Anticholinergic side effects are most often experienced in people who are taking antispasmodic medicationstricyclic antidepressants, and antipsychotic medications.

Antidepressants with Anticholinergic Effects:

The following medications are examples of antidepressants that are known to have anticholinergic effects:

Antispasmodics with Anticholinergic Effects:

The following antispasmodic medications are among those known to have anticholinergic effects:

Antipsychotic Medications with Anticholinergic Effects:

Other medications that may have anticholinergic effects include medications for Parkinson's disease, some antihistamines and some heart medications.

What to Do About Anticholinergic Side Effects

If you are experiencing side effects from your medication, speak with your doctor.

They can assess the degree of severity of your symptoms and make a decision as to whether to decrease your dosage or take you off the medication altogether. (Do not discontinue any medication without first speaking with your physician.) Another option for your physician is to switch out any of your other medications that might have anticholinergic effects so as to minimize any compounding effect.

If your side effect symptoms are mild, you may be able to minimize your discomfort by drinking plenty of water. To reduce the likelihood of constipation, be sure that you are eating foods that are high in dietary fiber.


Lieberman, J. "Managing Anticholinergic Side Effects" The Primary Care Companion to the Journal of Clinical Psychiatry 2004 6:20-23.

"Anticholinergics And Antispasmodics" Mayo Clinic Accessed January 9, 2015.

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