Imodium (loperamide) is a brand-name drug that’s used for treating diarrhea. Imodium has interactions with some other drugs and certain foods. Examples include certain antifungals, such as ketoconazole.
Imodium is available over-the-counter (OTC) and comes in different forms: oral tablet, oral capsule, and oral liquid solution. These forms have the same interactions.
Imodium is used to treat diarrhea in adults. The oral tablet and oral solution forms can be used in children ages 6 years and older. They may also be an option for children between ages 2 and 5 years depending on the recommendation from a doctor. Imodium oral capsule can be used in children ages 12 years and older.
An interaction occurs when one substance causes another substance to have a different effect than expected.
To learn more about Imodium’s interactions, keep reading. For additional information about Imodium, including details about its uses, see this article.
Before you start treatment with Imodium, tell your doctor and pharmacist which prescription, over-the-counter, and other medications you take. By sharing this information with them, you may help prevent possible interactions. (To learn whether Imodium interacts with supplements, herbs, or vitamins, see the “Imodium and other interactions” section.)
If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
Here’s a table of drugs that can interact with Imodium. Keep in mind that this table doesn’t include all drugs that may interact with Imodium. Some of these interactions are described in detail in “Drug interactions in depth.” You can also talk with your doctor or pharmacist to learn more about what not to take with Imodium.
| Drug class or drug name | Drug examples | Interaction result with Imodium |
| certain antiarrhythmic drugs | • amiodarone (Pacerone) • dofetilide (Tikosyn) | can increase the risk of long QT syndrome as a side effect of Imodium or certain antiarrhythmic drugs |
| certain antibiotics | • azithromycin (Zithromax) • levofloxacin | can increase the risk of long QT syndrome as a side effect of Imodium or certain antibiotics |
| certain antidepressants | • citalopram (Celexa) • escitalopram (Lexapro) | can increase the risk of long QT syndrome as a side effect of Imodium or certain antidepressants |
| certain antifungals | • ketoconazole • voriconazole (Vfend) | can increase the risk of long QT syndrome as a side effect of Imodium or certain antifungals |
| certain antimalarial drugs | • chloroquine • hydroxychloroquine (Plaquenil, Sovuna) | can increase the risk of long QT syndrome as a side effect of Imodium or certain antimalarial drugs |
| certain antipsychotic medications | • ziprasidone (Geodon) • thioridazine | can increase the risk of long QT syndrome as a side effect of Imodium or certain antipsychotics |
| certain kinase inhibitors | • nilotinib (Tasigna) • vandetanib (Caprelsa) | can increase the risk of long QT syndrome as a side effect of Imodium or certain kinase inhibitors |
| certain opioids | • methadone (Methadose) • buprenorphine (Butrans, others) | can increase the risk of long QT syndrome as a side effect of Imodium or certain opioids |
| cobicistat (Tybost) and treatments that contain it | •cobicistat/elvitegravir/emtricitabine/tenofovir disoproxil fumarate (Stribild) •cobicistat/darunavir/emtricitabine/tenofovir alafenamide (Symtuza) | can increase the risk of side effects of Imodium |
| ritonavir (Norvir) and treatments that contain it | • nirmatrelvir/ritonavir (Paxlovid) • lopinavir/ritonavir (Kaletra) | can increase the risk of side effects of Imodium |
There aren’t any known interactions between Imodium and alcohol. However, your doctor or pharmacist. may advise you to avoid or limit alcohol consumption during Imodium treatment.
This is because drinking alcohol while taking the drug may worsen some of Imodium’s side effects, including dizziness and fatigue.
Alcohol can also cause or worsen diarrhea, which is the condition Imodium is used to treat.
If you consume alcohol during Imodium treatment, these side effects may be more likely to occur. If you have questions about drinking alcohol while taking Imodium, talk with your doctor or pharmacist.
Here are some frequently asked questions about Imodium and possible interactions.
Can I take Pepcid and Imodium together?
Yes, it’s typically safe to take famotidine (Pepcid) and Imodium together. There aren’t reports of these medications interacting.
Pepcid is used to relieve heartburn and acid reflux symptoms. Imodium is used for diarrhea. Talk with your doctor or pharmacist if you have more questions about taking these medications together.
Does Imodium interact with paroxetine (Paxil)?
No, it’s not thought to. An interaction between Imodium and paroxetine (Paxil) hasn’t been reported.
Paroxetine is a selective serotonin reuptake inhibitor (SSRI). It’s prescribed to treat depression and certain other mental health conditions. Certain other SSRIs, such as citalopram (Celexa), can interact with Imodium. But this isn’t expected with paroxetine.
Talk with your doctor or pharmacist if you have questions about Imodium and interactions with antidepressants. You can also view the “Imodium interactions with other medications” section to learn more.
In some cases, factors or conditions could prevent your doctor or pharmacist from recommending Imodium due to the risk of harm. These are known as contraindications. The contraindications of Imodium include:
Having bloody or black stool
Imodium is prescribed to treat diarrhea. Having stool that’s bloody or black can be a sign of a serious condition, such as gastrointestinal (GI) bleeding. You shouldn’t use Imodium to treat diarrhea that is bloody or black. Immediately contact your doctor in this situation. If you have other symptoms, such as dizziness, shortness of breath, or fatigue, seek immediate medical attention.
Having had an allergic reaction to Imodium or any of its ingredients
If you have had an allergic reaction to Imodium or any of its ingredients, your doctor or pharmacist will likely not recommend Imodium. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better choices for you.
Note: Before you start treatment with Imodium, it’s important to tell your doctor or pharmacist if these contraindications apply to you. They can determine whether to recommend Imodium.
Here’s a closer look at certain drug interactions of Imodium.
Certain antifungal medications
Imodium can interact with certain antifungal medications, which are prescribed to treat fungal infections.
Interaction result:Taking Imodium with certain antifungal medications can increase the risk of long QT syndrome as a side effect of Imodium or certain antifungals. Long QT syndrome is a condition that affects the electrical rhythm of your heart. It can lead to arrhythmia that’s life threatening.
Interaction explained:Although rare, Imodium can affect your heart rhythm and cause long QT syndrome as a side effect. Certain antifungal drugs can also cause long QT syndrome. So, taking them with Imodium further raises the risk of this side effect.
Examples of antifungal drugs: Here are some antifungal drugs that may interact with Imodium:
- fluconazole
- itraconazole
- ketoconazole
- posaconazole
- voriconazole (Vfend)
Steps you or your doctor may take:It’s important to tell your doctor if you are taking Imodium. The antifungals listed above have a strong ability to cause long QT syndrome. If there’s a safer antifungal medication to take that doesn’t interact with Imodium and can treat your infection, your doctor will likely prescribe it instead. Or they may recommend you stop taking Imodium while you’re taking an antifungal listed above. In this case, they may recommend other treatments for diarrhea besides Imodium.
Certain antibiotic medications
Imodium can interact with certain antibiotic medications, which are prescribed to treat infections caused by bacteria.
Interaction result: Taking Imodium with certain antibiotic medications can increase the risk of long QT syndrome as a side effect of Imodium or certain antibiotics.
Interaction explained: Imodium can rarely cause long QT syndrome as a side effect. Certain antibiotic drugs can also cause long QT syndrome. Taking Imodium with an antibiotic that can also cause long QT syndrome raises your risk of this side effect.
Examples of antibiotic drugs: Here are some antibiotics that may interact with Imodium:
- azithromycin (Zithromax)
- clarithromycin
- ciprofloxacin (Cipro)
- erythromycin (Eryc, others)
- levofloxacin
Steps you or your doctor may take: Your doctor will avoid prescribing an antibiotic that can cause long QT syndrome if you’re also taking Imodium. If this isn’t possible, your doctor may suggest you stop taking Imodium while you’re taking the antibiotic. They may recommend other treatments for diarrhea besides Imodium.
Certain antiarrhythmic medications
Imodium can interact with certain antiarrhythmic medications, which are prescribed to treat heart arrhythmias.
Interaction result: Taking Imodium together with certain antiarrhythmic medications can increase your risk of developing long QT syndrome. Long QT syndrome is a side effect of Imodium and certain antiarrhythmic drugs.
Interaction explained: Rarely, Imodium can cause long QT syndrome as a side effect. Certain antiarrhythmic medications can also cause long QT syndrome as a side effect. So taking both medications together can further raise your risk of developing long QT syndrome.
Examples of antiarrhythmic drugs: Here are some antiarrhythmic drugs that may interact with Imodium:
Steps you or your doctor may take: Due to this risk, doctors typically avoid prescribing certain antiarrhythmics and Imodium together. They may recommend a different treatment for diarrhea besides Imodium or recommend an antiarrhythmic that doesn’t have this interaction. If you must use Imodium with certain antiarrhythmics, your doctor will likely monitor you closely for symptoms of long QT syndrome throughout treatment.
Imodium may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below. Keep in mind that the following information does not include all other possible interactions with Imodium.
Imodium interactions with supplements
Before you start treatment with Imodium, tell your doctor and pharmacist which supplements, herbs, and vitamins you take. By sharing this information with them, you may help prevent possible interactions.
If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
Imodium interactions with herbs
There are no specific reports of herbs interacting with Imodium. However, that doesn’t mean herbal interactions won’t occur or be recognized in the future. Because of this, it’s important to check with your doctor or pharmacist before taking any of these products during Imodium treatment.
Imodium interactions with vitamins
There are no specific reports of vitamins interacting with Imodium. However, that doesn’t mean vitamin interactions won’t occur or be recognized in the future. Because of this, you should talk with your doctor or pharmacist before taking any vitamin product with Imodium.
Imodium interactions with food
Grapefruit and grapefruit juice can interact with Imodium. Specifically, grapefruit products can stop your body from breaking down Imodium. This raises the level of Imodium in your body, which increases your risk of side effects from the drug, including arrhythmia. Due to this risk, your doctor or pharmacist may recommend not consuming grapefruit and grapefruit juice while taking the drug.
Imodium interactions with vaccines
There aren’t any known interactions between Imodium and vaccines. Talk to your doctor or pharmacist to see whether you’re due for any vaccines.
Imodium interactions with lab tests
Imodium isn’t known to interact with any lab tests. If you have concerns about this medication interacting with lab tests, talk to your doctor.
IMODIUM INTERACTION WITH CANNABIS OR CBDCannabis (often called marijuana) and cannabis products, such as cannabidiol (CBD), have been specifically reported to interact with Imodium. Using cannabis and taking Imodium can raise your risk of side effects of Imodium, including arrhythmia. This occurs because cannabis can increase the level of Imodium in your system.
Before you start treatment with Imodium, tell your doctor and pharmacist if you use cannabis. By sharing this information with them, you may help prevent possible interactions.
Note: Cannabis is illegal at a federal level but is legal in many U.S. states to varying degrees.
Certain medical conditions and other factors may increase the risk of interactions with Imodium. Before you take this drug, be sure to talk with your doctor or pharmacist about your health history. Imodium may not be the right treatment option if you have certain medical conditions or other factors affecting your health.
Health conditions or factors that might interact with Imodium include:
- Heart conditions, especially arrhythmia: Rarely, Imodium can cause arrhythmia as a side effect. If you have an existing heart condition, you may have a higher risk of this side effect if you take Imodium. And if you have an existing arrhythmia, taking Imodium could worsen your condition. Your doctor or pharmacist can help determine whether Imodium is safe for you to take.
- Liver problems, such as cirrhosis: Your body relies on your liver to break down Imodium after you take a dose. If you have a liver problem, such as cirrhosis, your body may not break down Imodium as well. This can cause an increased level of Imodium in your body, which may raise your risk of side effects of the drug. Your doctor or pharmacist can help determine whether Imodium is safe for you to take based on the severity of your liver problem.
- Allergic reaction: If you’ve had an allergic reaction to Imodium or any of its ingredients, your doctor or pharmacist will likely not recommend Imodium. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better choices for you.
- Breastfeeding: It’s not known whether it’s safe to take Imodium while breastfeeding. If you’re breastfeeding or planning to, talk with your doctor or pharmacist before taking Imodium. They can talk with you about treatment options and ways to feed your child.
- Pregnancy: It isn’t known whether Imodium is safe to take while pregnant. If you’re pregnant or planning to become pregnant, tell your doctor or pharmacist before starting Imodium. They can advise the right treatment for you.
You can take certain steps to help prevent interactions with Imodium. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. For example, you should plan to do the following:
- Let them know if you drink alcohol or use cannabis.
- Tell them about any other prescription or OTC medications you take, as well as any supplements, herbs, and vitamins.
- Create a
medication list , which your doctor and pharmacist can help you fill out.
It’s also important to read the Imodium directions and warnings on the packaging. If you need help reading or understanding this information, ask your doctor or pharmacist.
You can also help prevent interactions with Imodium by taking it exactly as your doctor or pharmacist recommends.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.