Lomotil (diphenoxylate / atropine) is an antidiarrheal combination medication containing diphenoxylate (an opioid) and atropine (an anticholinergic). It's used to treat diarrhea in people 13 years and older. You usually start by taking it 4 times a day until the diarrhea is under control, then switch to a lower dose. The medication is available in both brand-name and generic versions. Lomotil (diphenoxylate / atropine) is a controlled substance, so there might be specific requirements for getting it filled at the pharmacy. Side effects include sleepiness, dizziness, and nausea.
Add-on therapy for diarrhea for people 13 years and older
Lomotil (diphenoxylate / atropine) is a combination of two medications that work together to treat diarrhea.
Diphenoxylate is an opioid. It works by binding to specific proteins in your gut to help control and slow down gut movement.
Atropine is an anticholinergic that's used to prevent misuse of Lomotil (diphenoxylate / atropine). It blocks the activity of a natural chemical in your body called acetylcholine, which can cause bothersome side effects like nausea if Lomotil (diphenoxylate / atropine) is taken too often.
Source:Â DailyMed
Dose can be adjusted based on your symptoms
Can be taken with or without food
Comes as a tablet and solution that you take by mouth
Available as a lower-cost generic
Need to take multiple times a day in the beginning
Can't be used if diarrhea is caused by certain bacteria
Can cause serious side effects in young children
Potentially interact with a lot of medications
Start by taking Lomotil (diphenoxylate / atropine) by mouth 4 times a day, which is the maximum dose. Once the diarrhea is under control, your prescriber will likely recommend a lower dose. Most people see improvement within 48 hours.
Lomotil (diphenoxylate / atropine) is used in small doses to treat diarrhea and doesn’t cause morphine-like effects or addiction when used correctly. But, taking too much for a long time can affect your nervous system and cause dangerous withdrawal symptoms if stopped suddenly, like anxiety, sweating, chills, and irritability. Get medical help if you've taken more than prescribed.
Avoid alcohol while you're taking Lomotil (diphenoxylate / atropine). Alcohol and other medications that cause drowsiness (e.g., benzodiazepines, muscle relaxants, opioids) can worsen side effects of Lomotil (diphenoxylate / atropine).
Talk to your prescriber if your diarrhea hasn't improved within 10 days of taking Lomotil (diphenoxylate / atropine) at the maximum dose. They might want to try another medication to see if it will work better for you.
More tips for Lomotil (diphenoxylate / atropine) oral solution:
Only use the plastic dropper that comes with the solution to measure the dose of the oral solution. Don't use kitchen spoons or measuring spoons to measure your dose, since these might not be accurate.
The oral solution can be stored at room temperature. Once you've opened the bottle, throw any unused medication after 90 days.
Lomotil (diphenoxylate / atropine) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Children younger than 6 years old | Taking other medications that cause breathing problems
There have been cases of children having serious breathing problems or a coma after taking Lomotil (diphenoxylate / atropine). These effects can cause permanent brain damage or death. Children younger than 6 years old are at the greatest risk. Keep this medication safely stored and out of reach of children.
Risk factors: Taking higher doses of Lomotil (diphenoxylate / atropine)
Typical prescribed doses of Lomotil (diphenoxylate / atropine) for diarrhea don’t usually lead to addiction or misuse. However, higher doses can cause a life-threatening overdose. Symptoms include slow breathing, coma, extreme fatigue, slurred speech, and a rapid heartbeat. Slow breathing can appear up to 30 hours after taking the medication. Seek medical help immediately if you experience any of these symptoms.
Risk factors: Drinking alcohol | Taking other medications that make you sleepy
Lomotil (diphenoxylate / atropine) can make you feel sleepy or dizzy and it can lower your ability to focus, think, and react. Drinking alcohol and taking other medications that also cause sleepiness ((e.g., benzodiazepines, muscle relaxants, opioids) raises this risk. Avoid activities that require you to be alert, such as driving a car or operating machinery, until you know how this medication affects you.
Risk factors: Not taking in enough fluids | Severe diarrhea
Diarrhea can make you dehydrated. Make sure you get enough fluids when you have diarrhea and that you're properly hydrated when you take Lomotil (diphenoxylate / atropine). Talk to your prescriber or pharmacist if you have additional questions.
Risk factors: Having diarrhea caused by bacteria | Ulcerative colitis (UC)
In some cases, Lomotil (diphenoxylate / atropine) can lead to serious bowel problems. Lomotil (diphenoxylate / atropine) should never be used to treat diarrhea caused by bacteria. The medication slows down your gut, which can cause bacteria to grow more in your intestines. If you have worsening diarrhea after taking Lomotil (diphenoxylate / atropine), speak with your prescriber.
People who have ulcerative colitis (UC) should also be careful when taking Lomotil (diphenoxylate / atropine). It's rare, but this medication can cause a serious, life-threatening swelling of your large intestines called toxic megacolon. Let your prescriber know if you have symptoms such as a fever, high heart rate, dehydration, or low blood pressure.
Each tablet contains 2.5 mg of diphenoxylate and 0.025 mg of atropine, and the oral solution contains the same amount of each ingredient in 5 mL.
People 13 years and older: The typical starting dose is 2 tablets by mouth four times a day. Once the diarrhea is controlled, your prescriber will recommend a lower dose to manage your symptoms (e.g., 2 tablets once daily).
People 13 years and older: The typical starting dose is 10 mL by mouth four times a day. Once the diarrhea is controlled, your prescriber will recommend a lower dose to manage your symptoms (e.g., 10 mL once daily).
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Children younger than 6 years old
Diarrhea caused by a bacteria
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Centers for Disease Control and Prevention. (n.d). PROTECT your child: Use the right tool to give the right dose.
Department of Justice/Drug Enforcement Administration. (2020). Narcotics.
Hikma Pharmaceuticals USA Inc. (2023). Diphenoxylate hydrochloride and atropine sulfate solution [package insert]. DailyMed.
Jain, M., et al. (2024). Diphenoxylate and atropine. StatPearls.
Lannett Company, Inc. (2024). Diphenoxylate hydrochloride and atropine sulfate tablet [package insert]. DailyMed.
Skomorochow, E., et al. (2023). Toxic megacolon. StatPearls.
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