Cialis interactions: Alcohol, medications, and other factors

Cialis (tadalafil) is a brand-name prescription drug used in males* to treat erectile dysfunction and symptoms of benign prostatic hyperplasia.

As with other medications, Cialis can interact with certain other drugs, foods, and alcohol. An interaction occurs when one substance causes another substance to have a different effect than expected.

For details about Cialis’s interactions, keep reading. For additional information about Cialis, see this article.

* Sex and gender exist on spectrums. Use of the term “male” in this article refers to sex assigned at birth.

In some cases, a factor or condition could prevent your doctor from prescribing Cialis due to the risk of harm. This is known as a contraindication. The contraindications of Cialis include:

Taking a guanylate cyclase stimulator

Doctors are not likely to prescribe Cialis with guanylate cyclase (GC) stimulators. These medications are used to treat pulmonary arterial hypertension. (This is a form of high blood pressure in the arteries of the lungs.)

Both Cialis and GC stimulators may lower blood pressure. Taking Cialis in combination with a GC stimulator could lower your blood pressure further.

Examples of GC stimulators that can interact with Cialis include vericiguat (Verquvo) and riociguat (Adempas).

If you’re taking a GC stimulator, talk with your doctor before taking Cialis. They can recommend a treatment other than Cialis for your condition.

Taking a nitrate

Doctors are not likely to prescribe Cialis with nitrates. These medications are used to help prevent or treat angina (a type of chest pain).

Both Cialis and nitrates can lower blood pressure. Taking Cialis in combination with a nitrate may lower blood pressure further. A sudden drop in blood pressure can lead to fainting and dizziness. In severe cases, it may lead to heart attack or stroke.

Examples of nitrates that can interact with Cialis include:

• isosorbide mononitrate (Monoket)
• isosorbide dinitrate (Isordil)
• nitroglycerin (Nitro-Dur, NitroMist, Nitrostat)

In addition to the medications above, nitrates also include a group of drugs called poppers. An example of a popper is amyl nitrate.

If you’re taking a nitrate, talk with your doctor before taking Cialis. They can advise you on treatments other than Cialis for your condition.

Having had an allergic reaction to Cialis or any of its ingredients

If you have had an allergic reaction to Cialis or any of its ingredients, your doctor will likely not prescribe Cialis. Taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices.

Note: Before you start treatment with Cialis, it’s important to tell your doctor if any of these contraindications apply to you. They can determine whether to prescribe Cialis.

Doctors may recommend limiting the amount of alcohol you consume while taking Cialis. This is because both alcohol and Cialis can lower blood pressure. Drinking alcohol during Cialis treatment could lower blood pressure further.

If you drink alcohol, talk with your doctor before taking Cialis. They can recommend an amount, if any, that’s safe to consume during your treatment.

Before you start treatment with Cialis, 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.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Here’s a chart of drugs that can interact with Cialis. Due to the risk of interactions, doctors may not prescribe Cialis with these medications. Keep in mind that this chart does not include all drugs that may interact with Cialis. Some of these interactions are described in detail just below in “Drug interactions in depth.”

* For details about this interaction, see “When to avoid Cialis” above.
† To learn about possible side effects of Cialis, see this article.

Here’s a closer look at certain drug interactions of Cialis.

PDE5 inhibitors

Phosphodiesterase 5 (PDE5) inhibitors are medications used to treat conditions such as pulmonary arterial hypertension and erectile dysfunction.

Interaction result. Taking a PDE5 inhibitor with Cialis can increase the risk of low blood pressure.

Interaction explained. Cialis belongs to a class of drugs called PDE5 inhibitors. Medications in this class, including Cialis, can lower blood pressure. Taking Cialis with other drugs in the same drug class can increase the risk of low blood pressure further.

Examples of PDE5 inhibitors. PDE5 inhibitors that may interact with Cialis include the following:

• avanafil (Stendra)
• vardenafil (Staxyn)
• sildenafil (Viagra, Revatio)
• other forms of tadalafil (Adcirca, Alyq)

Steps you or your doctor may take. Due to this risk, doctors typically will not prescribe Cialis in combination with other PDE5 inhibitors. Before taking Cialis, it’s important to tell your doctor if you’re already taking a PDE5 inhibitor. They’ll likely prescribe a treatment other than Cialis for your condition.

Certain antibiotic drugs

Antibiotic drugs are used to treat infections caused by bacteria.

Interaction result. Taking Cialis with certain antibiotics can increase the risk of side effects of Cialis. (To learn more about the side effects of Cialis, see this article.)

Interaction explained. Certain antibiotics can prevent your body from breaking down Cialis. This can result in a higher level of the drug in your body than usual. A high level of the drug in your system could increase risk of side effects from Cialis.

Examples of antibiotic drugs. Below are a few antibiotics that may interact with Cialis:

• clarithromycin
• erythromycin (E.E.S., EryPed, Ery-Tab, others)
• rifampin (Rifadin, Rimactane)

Steps you or your doctor may take. If you’re taking an antibiotic, talk with your doctor before starting Cialis treatment. They can advise you on whether it’s safe for you to take Cialis with these medications.

Certain antiseizure drugs

Antiseizure drugs are used to treat seizure disorders such as epilepsy.

Interaction result. Taking Cialis with certain antiseizure drugs can make Cialis less effective than usual.

Interaction explained. Certain antiseizure drugs may cause your body to break down Cialis more quickly than usual. This could result in a lower level of the drug in your body than usual, which could make the drug less effective for treating your condition.

Examples of antiseizure drugs. Antiseizure drugs that may interact with Cialis include those listed below:

• carbamazepine (Carbatrol, Epitol, Tegretol, others)
• phenobarbital
• phenytoin (Dilantin, Phenytek)

Steps you or your doctor may take. Before taking Cialis, tell your doctor if you’re taking antiseizure drugs. They can advise you on whether these medications may interact with Cialis.

Cialis may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below.

Cialis and supplements

It’s possible for drugs to interact with supplements such as vitamins and herbs.

Cialis and herbs

Taking Cialis with an herb called St. John’s wort can decrease how well Cialis works. The herb is sometimes used to treat depression.

Be sure to talk with your doctor about taking both St. John’s wort and Cialis. Your doctor may be able to provide you with alternative treatment options.

Cialis and vitamins

No vitamin interactions have been reported with Cialis. You should still check with your doctor or pharmacist before taking any vitamins during Cialis treatment.

Cialis interactions with food

Drinking grapefruit juice or eating grapefruit while taking Cialis could raise the level of Cialis in your body. A higher level of the drug could increase your risk of side effects. (To learn about possible side effects of Cialis, see this article.)

If you have questions about taking Cialis with other foods or drinks, such as coffee, talk with your doctor or pharmacist.

Cialis and vaccines

Vaccines have not been reported to interact with Cialis. If you have questions about getting certain vaccines during your Cialis treatment, talk with your doctor or pharmacist.

Cialis and lab tests

There are no specific reports of lab tests interacting with Cialis. For more information about having certain lab tests while taking Cialis, talk with your doctor or pharmacist.

Cialis interaction with cannabis or CBD

Cannabis (marijuana) and cannabis products, such as cannabidiol (CBD), have been specifically reported to interact with Cialis.

The exact effect of cannabis products on Cialis may vary from person to person. In some cases, cannabis products may decrease the level of Cialis in the body, which could cause the drug to be less effective than usual.

In other cases, cannabis products may raise the level of Cialis in the body. This could increase your risk of side effects from Cialis. (To learn about possible side effects of Cialis, see this article.)

Before you start treatment with Cialis, tell your doctor and pharmacist if you take 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 states to varying degrees.

Certain medical conditions and other factors may increase the risk of interactions with Cialis. Before you take Cialis, be sure to talk with your doctor about your health history. Cialis may not be the right treatment option for you if you have certain medical conditions or other factors affecting your health.

Health conditions or factors that might interact with Cialis include the following:

Misshaped penis. Before starting treatment with Cialis, tell your doctor if you have a condition that affects the shape of your penis, such as Peyronie’s disease. Such conditions can increase your risk of priapism as a side effect. Your doctor can help determine whether Cialis is a safe treatment option for you.

Heart problems or stroke. Doctors typically will not prescribe Cialis if you have a heart problem or have had a stroke. Examples of heart problems include having heart failure in the past 6 months or a heart attack in the past 90 days.

Cialis is also not recommended in people with problems such as:

• untreated low or high blood pressure
• untreated abnormal heart rhythm
• chest pain that occurs during sex

It’s not known whether Cialis is safe if you have any of these conditions. If you do, your doctor will likely prescribe a treatment other than Cialis.

Liver or kidney problems. If you have a liver or kidney problem, be sure to tell your doctor before taking Cialis. Examples of these problems include liver failure and kidney failure. Your doctor may give you a lower dosage of Cialis than what’s typically prescribed. (For details about the dosage of Cialis, see this article.)

Bleeding problems. Before taking Cialis, tell your doctor if you have a bleeding problem. An example is hemophilia. Your doctor can advise you on whether Cialis is a safe treatment option for you.

Blood cancers or blood cell problems. Before taking Cialis, tell your doctor if you have a blood cancer. Examples include multiple myeloma and leukemia. Also tell them if you have certain blood cell problems, such as sickle cell anemia. These conditions could increase your risk of priapism as a side effect. Your doctor can help determine if Cialis is right for you.

Peptic ulcers. If you have a peptic ulcer, talk with your doctor before taking Cialis. You may have an increased risk of bleeding with the drug. Your doctor can advise you on whether Cialis is safe to take.

Eye problems. In rare cases, Cialis can cause vision loss or other serious eye problems. If you already have an eye problem, you may have an increased risk of eye side effects with the drug. Before taking Cialis, tell your doctor if you have a problem with your retina or optic nerve. This includes conditions such as retinitis pigmentosa. They can help determine whether it’s safe for you to take Cialis.

Allergic reaction. If you’ve had an allergic reaction to Cialis or any of its ingredients, your doctor will likely not prescribe Cialis. For details, see “When to avoid Cialis” above.

Pregnancy. Cialis is not approved for use in females.* It’s not known if the drug is safe to use during pregnancy. You can talk with your doctor to learn more.

Breastfeeding. Cialis is not approved for use in females.* It’s not known if Cialis passes into breast milk. For additional information about Cialis and breastfeeding, talk with your doctor.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to sex assigned at birth.

Here are some frequently asked questions about Cialis and possible interactions.

Does Cialis interact with NSAIDs, such as ibuprofen or meloxicam?

There’s no known interaction between Cialis and nonsteroidal anti-inflammatory drugs (NSAIDs). Although NSAIDs are typically used to treat pain, they can also be used for inflammation.

Examples of NSAIDs include:

• ibuprofen (Advil, Motrin, others)
• meloxicam (Anjeso, Mobic)
• naproxen (Aleve, Naprosyn)
• celecoxib (Celebrex, Elyxyb)
• diclofenac (Cambia, Cataflam, Zipsor, others)

If you’re interested in treating inflammation or pain while taking Cialis, talk with your doctor or pharmacist.

Can I drink coffee while taking Cialis?

Coffee and Cialis are not known to interact with each other.

Coffee often contains high amounts of caffeine. The results of one study found that consuming caffeine may lower the risk of erectile dysfunction (ED), which Cialis is used to treat. However, it’s unknown whether coffee or caffeine is effective for treating this condition.

If you’d like to learn more about Cialis and coffee, talk with your doctor.

Do Cialis and finasteride interact?

Cialis is not known to interact with the drug finasteride (Propecia, Proscar). Finasteride is used to treat conditions such as baldness and benign prostatic hyperplasia.

Finasteride may cause ED as a side effect. Cialis is used to treat ED. If you develop ED while taking finasteride, your doctor may prescribe medication to ease the side effect. This may include Cialis. Your doctor can tell you more.

Is there an interaction between Cialis and Xanax?

There’s no known interaction between Cialis and alprazolam (Xanax).

Xanax may cause sexual side effects, including changes in libido (sex drive). Having a low libido could result in ED. Therefore, it’s possible that taking Xanax could result in ED. If you have ED due to Xanax, your doctor may prescribe Cialis to treat your condition.

If you have other questions about Cialis and Xanax, talk with your doctor or pharmacist.

Can I take Cialis with omeprazole?

Cialis and omeprazole (Prilosec) are not known to interact with each other. Omeprazole is used to treat certain digestive problems, such as acid reflux.

The results of one report suggest that ED is a possible side effect of omeprazole. If you have ED that’s related to omeprazole, your doctor can recommend the right treatment option for you. This may include taking Cialis.

You can take certain steps to help prevent interactions with Cialis. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. For example, you should plan the following:

• Let them know if you drink alcohol or take cannabis.
• Tell them about any other 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 label of Cialis and other paperwork that comes with the drug. The label may have colored stickers that mention an interaction. And the paperwork, sometimes called the prescribing information, may contain details about interactions. If this information is difficult to understand, ask your doctor or pharmacist to help explain it.

You can also help prevent interactions with Cialis by taking it exactly as your doctor prescribes.

Besides learning about interactions, you may want to find out more about Cialis. These resources might help:

• Overview of Cialis. For a general overview of Cialis, read this article.
• Side effects. If you’re interested in the side effects of Cialis, see this article. Another option is to refer to the Cialis prescribing information.
• Dosage specifics. You can refer this article to learn about the dosage of Cialis.
• Drug comparison. Find out how Cialis compares with Viagra, Levitra, and Adcirca.
• Facts about your condition. To learn more about your condition, see our men’s health hub.

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.