9 Dicyclomine Side Effects You Should Know About

Dicyclomine (Bentyl) is a medication that helps relieve stomach pain and bloating caused by irritable bowel syndrome (IBS). It's typically taken as needed when symptoms flare, but it's not a first-choice medication for treating IBS. One reason for this is that side effects are common when taking dicyclomine. Here, we'll review what dicyclomine side effects to expect and which ones you should be concerned about.

Dicyclomine side effects at a glance

Below are the common and rare dicyclomine side effects reported in clinical studies. Keep in mind that you may experience side effects other than those listed here. Your healthcare team can answer any questions or concerns about side effects you experience.

Common dicyclomine side effects include:

• Dizziness

• Dry mouth

• Blurry vision

• Nausea

• Drowsiness

• Weakness

• Anxiety

• Insomnia

• Constipation

• Trouble peeing

• Fast heart rate

Rare but serious dicyclomine side effects include:

• Shortness of breath

• Heart palpitations or arrhythmias (irregular heartbeat)

• Confusion or disorientation

• Hallucinations (seeing or hearing things that aren't there)

• Trouble swallowing or talking

• Increased risk of heat stroke

Dicyclomine may not be appropriate for adults ages 65 and older - side effects are more likely for this age group. Let's look more closely at nine dicyclomine side effects and how to manage them.

1. Dizziness

Dizziness is one of the most common dicyclomine side effects. In clinical trials, 40% of people taking dicyclomine reported feeling dizzy.

This happens because dicyclomine is an anticholinergic medication. It blocks the effects of a chemical called acetylcholine in the body to help lessen muscle spasms in your gut. But blocking acetylcholine also leads to a number of side effects, because it works on many different areas of your body.

Dizziness can lead to falls, especially in older adults. If you're feeling dizzy while taking dicyclomine, find somewhere to sit and rest until your dizziness improves. Then, slowly stand up once you're feeling more steady on your feet. Try to avoid sudden changes in position. You should also avoid driving or other activities that require coordination until you know how dicyclomine affects you.

Your dizziness may improve over time as your body adjusts to dicyclomine. But if it becomes severe or doesn't get better, contact your prescriber. They may need to lower your dosage or try a different treatment option.

2. Dry mouth

Dry mouth is another anticholinergic dicyclomine side effect. You may have trouble swallowing or a bad taste in your mouth along with it.

Dry mouth typically isn't serious, but it can be bothersome. Drinking plenty of fluids and avoiding alcohol and tobacco can help prevent dry mouth. Chewing sugar-free gum can help, too. If these tactics don't work, you may want to try an over-the-counter (OTC) saliva substitute product, such as Biotene. Be sure to get regular dental care, too, because dry mouth can make tooth decay more likely.

3. Blurry vision

You may have blurry vision while taking dicyclomine. This is another anticholinergic side effect. Dicyclomine can dilate your pupils, similar to the drops used during an eye exam. It can also make your eyes dry, which can contribute to blurry vision.

As with dizziness, use caution when driving or walking until you know how dicyclomine affects your vision. If your symptoms are severe or don't improve, let your prescriber know. Keep in mind that dicyclomine can worsen glaucoma symptoms, so you shouldn't take it if you have a history of glaucoma.

4. Nausea

Nausea is another possible dicyclomine side effect. It's not clear why this happens, but nausea is a common IBS symptom. And it's also associated with constipation, another side effect of both dicyclomine and IBS. So it could have a number of different causes.

You can take dicyclomine with or without food. But taking it with food may help lessen nausea. Staying hydrated, avoiding spicy or fried foods, and eating smaller meals may also help. Peppermint oil is a home remedy that may help with both nausea and IBS symptoms.

If your nausea is severe or doesn't improve, let your prescriber know. They can help determine the cause and the best next steps to manage it.

5. Drowsiness

Drowsiness is another possible dicyclomine side effect. In some cases, you may also feel weak or lack the energy to perform daily tasks.

It's best not to drive or do activities that require alertness until you know how dicyclomine affects you. It's also a good idea to take your first dose on a day you can stay home and relax, just in case.

In most cases, your drowsiness should resolve as you get used to taking dicyclomine. But if it becomes severe or interrupts your daily life, talk to your prescriber. They can help determine if dicyclomine is to blame and provide an alternative medication if needed.

Good to know: Some people taking dicyclomine may have trouble sleeping or feel more nervous or agitated than usual instead of feeling sleepy. In most cases, these are mild side effects that improve on their own. But they can also be a sign of anticholinergic toxicity - more on that below.

6. Constipation

Anticholinergics such as dicyclomine commonly cause constipation. If diarrhea is a common IBS symptom for you, this side effect may actually be helpful. But if constipation is your main IBS symptom, dicyclomine may not be your best treatment option.

In most cases, you can manage constipation on your own at home. Getting more fiber in your diet, drinking plenty of fluids, and exercising can all help. If needed, an OTC laxative, such as polyethylene glycol (Miralax), can help. Just make sure your prescriber OKs it.

Seek medical care if your constipation persists or if you have severe stomach pain or rectal bleeding along with it.

7. Heart rate and blood pressure changes

Dicyclomine can speed up your heart rate and increase your blood pressure. You may not notice this side effect. But in some cases, you may feel heart palpitations or develop a headache.

Be sure to let your prescriber know if you have a history of heart-related conditions before you start taking dicyclomine. If you have chest pain or notice a change in your heartbeat along with dizziness while taking it, call 911 or seek emergency care.

8. Increased risk of heat stroke

Dicyclomine reduces your ability to sweat. That can increase your risk of heat-related illness, especially when it's very hot outside or when you exercise with intensity. Early symptoms include muscle cramps, nausea, and weakness or dizziness.

If not treated, more severe symptoms can occur, such as:

• Dry, red skin

• Confusion

• High body temperature (over 103°F)

• Seizures

• Loss of consciousness

Take steps to avoid extreme temperatures and stay out of direct sunlight on hot days. Seek medical attention immediately if you think you're experiencing heat-related illness while taking dicyclomine.

9. Anticholinergic toxicity

In rare cases, the combined anticholinergic dicyclomine side effects can lead to anticholinergic toxicity. This is more likely in older adults or if you're taking high doses or other medications with similar side effects. Reviewing your medication list with your healthcare team can help lessen the risk of this side effect.

The classic signs of anticholinergic toxicity are included in the following memory device:

• Red as a beet (flushed skin)

• Dry as a bone (dry mouth, eyes, and skin)

• Blind as a bat (dilated pupils, blurry vision)

• Mad as a hatter (confusion, delirium, agitation)

• Hot as a hare (overheating and fever)

• Full as a flask (trouble peeing)

If you or a loved one develops symptoms of anticholinergic toxicity, call 911 or seek emergency care. You can also contact Poison Control at 1-800-222-1222.

Is dicyclomine hard on the kidneys?

No. Dicyclomine isn't known to cause kidney problems for most people. But in some cases, it may make it harder to pee (urinary retention). And over time, this could lead to kidney problems if it isn't treated. So if you're peeing less than usual or aren't able to pee at all while taking dicyclomine, you should contact your prescriber right away.