Cialis (Tadalafil) Dosages: Your GoodRx Guide

Cialis (tadalafil) is a prescription phosphodiesterase-5 (PDE-5) inhibitor medication. It’s approved for treating erectile dysfunction (ED) and benign prostatic hyperplasia (BPH) in men. Cialis comes as a tablet taken by mouth daily or as needed, depending on the use.

In this guide, we’ll review typical Cialis dosages for ED and BPH. Keep in mind that you might take Cialis differently, depending on your health history or other factors. And if you’re taking tadalafil for pulmonary arterial hypertension, those dosages will be covered in a different article. Your healthcare provider can answer your questions about the right Cialis dosage for you.

What’s the typical Cialis dosage?

The typical Cialis dosage for adults depends on why you’re taking it. And no matter what you’re treating, you can take your dose with or without food.

Erectile dysfunction

Cialis can be taken a few different ways for ED. One way is taking a dose as needed before sex. In this case, it may take up to 2 hours to work. The other way is taking lower-dose Cialis every day — whether you’re planning to have sex or not.

As-needed dosing 

The usual as-needed Cialis dosage for ED ranges from 5 mg to 20 mg by mouth, taken at least 30 minutes before sex. You’ll typically start with the 10 mg dose, which your healthcare provider may adjust up or down depending on your response. Cialis’ effects can last for up to 36 hours. So, it’s not recommended to take more than one dose per day.

Daily dosing 

Another option is to take Cialis on a daily basis for ED. The usual daily Cialis dosage ranges from 2.5 mg to 5 mg by mouth, taken once daily. Most people start at the 2.5 mg dose, which may be increased to 5 mg based on how well it works for you. With daily dosing, be sure to take your dose at the same time every day.

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Benign prostatic hyperplasia

For treating BPH symptoms, the usual Cialis dosage is 5 mg by mouth once daily. If you’re treating both BPH and ED, you’ll take this same dose. Remember to take your Cialis dose at the same time every day. 

Are there any dosage adjustments for medical conditions or interactions?

There are several factors that may require an adjustment to your Cialis dosage. This includes kidney problems, liver problems, and drug interactions, as described below.

Dosage for people with kidney problems

Cialis is partially removed from the body by your kidneys. So, people with kidney problems may be more likely to experience Cialis side effects since the medication can build up in the body. In this case, you may need to take a lower dosage.

If you have kidney problems, your healthcare provider may run a blood test called creatinine clearance (CrCl) to estimate how well your kidneys are working. This will typically determine your Cialis dosage.

Dosage for people with liver problems

Cialis is broken down by liver enzymes (proteins). If you have liver problems, this can also increase the amount of Cialis in your body after taking a dose. 

For people with mild to moderate liver problems, the maximum Cialis dosage for ED is 10 mg by mouth as needed before sex. Taking Cialis as needed isn’t recommended if you have severe liver problems.

Once-daily Cialis hasn’t been studied very much in people with any kind of liver disease. If you have mild to moderate liver problems, Cialis should be used with caution. And if you have severe liver problems, Cialis isn’t recommended.

Dosage adjustments for drug interactions

There are a few medications that interact with Cialis. Some interactions, like nitrates, should be avoided entirely. But others may require dosage adjustments, including:

• Alpha blockers: If you’re adding Cialis to an alpha blocker, it’s recommended to start with the lowest dose (for ED only). Cialis and alpha blockers shouldn’t be taken together for BPH.

• Ketoconazole: The maximum Cialis dosage with ketoconazole is 10 mg once in a 72-hour period for as-needed dosing, or 2.5 mg for daily dosing.

• Ritonavir (Norvir; part of Paxlovid): The maximum Cialis dosage with ritonavir is the same as ketoconazole above.

These are just a few examples. Keep your healthcare provider and pharmacist informed about your current medication list. They can help flag potential interactions ahead of time.

What happens if you miss a dose of Cialis?

If you’re taking Cialis every day and miss your dose, take it as soon as possible on the same day. But if you don’t realize a forgotten dose until the next day, skip it and continue with your next scheduled dose. Never double your dose or take more than one dose in a day.

What should you do if you take too much Cialis?

Taking too much Cialis can increase your risk of side effects. This can include headache, flushing, and upset stomach. Low blood pressure (hypotension) that makes you feel dizzy or lightheaded is also possible

If you think you may have taken too much Cialis, call your healthcare provider or Poison Control at 1-800-222-1222. If you have an erection lasting more than 4 hours (called priapism), this is a serious side effect and a medical emergency — you should go to the nearest emergency room.

How to save on Cialis

Cialis is available as a brand-name medication and lower-cost generics. GoodRx can help you save over 90% off the average retail price at certain pharmacies. You could pay as little as $8.76 for generic Cialis with GoodRx.

Why trust our experts?

Written by:

Brian Leonard, PharmD, BCACP, BCGP

Brian Leonard earned his doctorate in pharmacy from the University of Florida College of Pharmacy and is board certified in Ambulatory Care and Geriatric Pharmacy.

Edited by:

Alyssa Billingsley, PharmD

Alyssa Billingsley, PharmD, is the director of pharmacy content for GoodRx. She has over a decade of experience as a pharmacist and has worked in clinical, academic, and administrative roles.

Reviewed by:

Austin Ulrich, PharmD, BCACP

Austin Ulrich, PharmD, BCACP, is a board-certified ambulatory care clinical pharmacist. In his early career, he provided direct patient care in a variety of settings, including hospital and community pharmacies, and in a primary care clinic as a clinical pharmacist.

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