Key takeaways

  • Cialis is available in tablet form in strengths of 2.5 milligrams (mg), 5 mg, 10 mg, and 20 mg. The dosage varies depending on the condition being treated and whether it’s prescribed for occasional or daily use.
  • For erectile dysfunction, Cialis can be taken occasionally as needed (10 mg, adjusted to 5 mg or 20 mg) or daily (2.5 mg, adjusted to 5 mg). But it should not be taken more than once per day.
  • For benign prostatic hyperplasia, the recommended dose of Cialis for once daily use is 5 mg, taken at approximately the same time every day.

Cialis (tadalafil) is a prescription drug used to treat erectile dysfunction and symptoms of benign prostatic hyperplasia.

The active ingredient in Cialis is tadalafil. (An active ingredient is what makes a medication work.) Cialis belongs to a group of drugs called phosphodiesterase type 5 inhibitors.

This article describes the dosages of Cialis, as well as its strengths and how to take it. To learn more about Cialis, including its cost and side effects, see this Cialis overview article.

Your doctor will likely start you on a low dosage of Cialis and adjust it over time to reach the right amount for you. They’ll ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly used or recommended for Cialis. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs. In some cases, doctors may adjust your dosage from those described here.

Cialis form

Cialis is available as an oral tablet that you swallow.

Cialis strengths

Cialis tablets come in four strengths:

  • 2.5 milligrams (mg)
  • 5 mg
  • 10 mg
  • 20 mg

Cialis is approved by the Food and Drug Administration (FDA) to treat the following:

The prescribed Cialis dosage may vary depending on the condition it’s being used to treat. Always follow your doctor’s instructions. Notify them if you experience any Cialis side effects that may prevent you from taking your medication.

Dosage for erectile dysfunction (ED)

There are two dosage options when Cialis is used to treat ED: dosage for occasional (as needed) use and for daily use.

Occasional use for ED

With occasional use, you’ll take Cialis only as needed. You’ll likely take one 10-mg tablet before sexual activity.

Depending on how well the 10-mg dose works for your ED, your doctor may adjust your dose. It may be decreased to 5 mg or increased to 20 mg. You’ll continue to take it only as needed before sexual activity.

You should not take Cialis more than once per day. You also should not take more than the recommended maximum dosage of Cialis, which is 20 mg per day. Taking higher dosages of Cialis than this, such as 40 mg per day, raises your risk of serious side effects. Examples of these side effects include very low blood pressure and priapism (a painful erection lasting 4 hours or longer).

Daily use for ED

With daily use, you’ll take one dose of Cialis per day. You don’t need to time your dose to be taken before sexual activity. You should take it around the same time each day.

For daily use of Cialis for ED, the usual starting dosage is 2.5 mg per day. If this dosage isn’t effective for you, your doctor may increase your dosage to 5 mg per day.

Dosage for benign prostatic hyperplasia (BPH)

When used for benign prostatic hyperplasia (BPH), the recommended dose of Cialis for once daily use is 5 mg, taken at approximately the same time every day.

When Cialis is prescribed along with the drug finasteride for BPH, the recommended Cialis dose for once daily use is 5 mg, taken at approximately the same time every day for up to 26 weeks.

Dosage for ED and BPH

If your doctor prescribes Cialis to treat ED along with BPH symptoms, you’ll take Cialis once per day.

For this use, the usual dosage is 5 mg per day. You should not take any additional doses of Cialis for occasional use before sexual activity.

You don’t need to time your dose to be taken before sexual activity. You should take it around the same time each day.

Dosage adjustments

If you have certain kidney problems or liver problems, your doctor may prescribe a lower dosage of Cialis for you. This is because with your condition, the usual dosage may raise your risk of side effects from the drug.

Depending on how severe your kidney or liver problems are, your doctor may recommend occasional dosing instead of daily dosing to treat ED.

You’ll take Cialis by swallowing it, either once per day or occasionally (as needed before sexual activity).

The Cialis tablet should be swallowed whole. You can take it with or without food.

With once-daily Cialis, be sure to take it around the same time each day. When you’re taking Cialis once a day, there isn’t a best time to take Cialis. But taking your dose around the same time each day helps to keep a steady level of the drug in your body.

For occasional (as needed) use for ED, take one Cialis tablet at least 30 minutes before anticipated sexual activity. In most cases, the ability to have sexual intercourse will be increased for up to 36 hours.

If you have questions about taking Cialis, talk with your doctor or pharmacist.

How long do you take Cialis?

Cialis is usually a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term once you reach your maintenance dose.

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If your doctor prescribes once-daily Cialis for your condition, it’s best to take it around the same time each day. If you miss a dose, take it as soon as possible.

However, you should not take more than one dose of Cialis per day. Doing so could raise your risk of side effects, such as low blood pressure or priapism (a painful erection lasting 4 hours or longer).

If you need help remembering to take your dose of Cialis on time, try using a medication reminder. This can include setting an alarm or downloading a reminder app on your phone. A kitchen timer can work, too.

Do not take more Cialis than your doctor prescribes, as this can lead to harmful effects.

What to do in case you take too much Cialis

Call your doctor right away if you think you’ve taken too much Cialis. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.

The following are answers to some commonly asked questions about Cialis dosage.

How can I get the maximum effect from Cialis?

To get the maximum effect from Cialis, take it exactly as prescribed.

If you’re using once-daily Cialis for either erectile dysfunction (ED) or benign prostatic hyperplasia (BPH), take your dose around the same time each day. This helps keep a consistent amount of the drug in your body to provide the maximum effect. If you forget to take doses, skip doses, or take doses late, the medication won’t work as well.

When prescribed for ED, take one Cialis tablet at least 30 minutes before anticipated sexual activity. In most cases, the ability to have sexual intercourse will be increased for up to 36 hours.

If you have other questions about how to get the most from Cialis, talk with your doctor or pharmacist.

If I take 5 milligrams (mg) of Cialis daily, how long does it take the drug to work?

Cialis starts working quickly. Studies show that the drug begins to work 30 minutes to 6 hours after you take your first dose. But it may take several days for the medication to reach its full effectiveness. If you don’t notice a reduction in your BPH symptoms or ED within a week of daily use, talk with your doctor. They may need to adjust your dosage.

Could I take an 80-mg dose of Cialis?

No, it’s not safe to take an 80-mg dose of Cialis. The maximum recommended daily dosage of Cialis is 20 mg per day if you take it as needed for ED. If you take Cialis daily, the maximum dosage is 5 mg per day.

Taking doses of Cialis over the recommended limit could lead to serious side effects, such as dangerously low blood pressure or priapism (a painful erection lasting 4 hours or longer).

What’s the typical Cialis dosage for a 70 year old?

Cialis dosage is not based on your age alone. Instead, your doctor will prescribe the dosage that’s best for your condition. Before prescribing Cialis, your doctor may send you for a blood test to check how well your kidneys and liver are working. This is because they’ll take your kidney and liver health into consideration when determining your dosage.

For many people, their kidneys may not work as well as they age. So if you’re an older adult (age 65 years or older), it may take longer for your body to break down and clear Cialis from your system. Older adults’ bodies also be more sensitive in how they react to Cialis, which may increase their risk of side effects.

If you’re 70 years old, your doctor will likely start you on a low dosage of Cialis. If it works well for you, you’ll probably continue taking a low dosage. If it doesn’t work well for you or you develop bothersome side effects, your doctor will adjust your dosage. The goal is to find the lowest dosage that effectively treats your BPH symptoms or ED without causing bothersome side effects.

If you have questions about what your Cialis dosage should be, talk with your doctor.

How do the dosages for Cialis and Viagra compare?

As ED treatments, both Cialis and Viagra can be taken occasionally (as needed) before sexual activity. The usual dosage for occasional Cialis use is one 10-mg tablet at least 30 minutes before anticipated sexual activity. The usual dosage for occasional Viagra use is one dose 1 hour before sexual activity.

Cialis is also approved for once-daily dosing for ED, but Viagra is not. This is because the effects of Cialis on ED can last much longer than Viagra’s effects. One dose of Cialis can help with erectile function for up to 36 hours. In comparison, Viagra’s effects can last up to 4 hours. But on average, its effects start to reduce 2 to 3 hours after you take a dose.

The typical dose for once-daily Cialis for ED is 2.5 milligrams (mg) to 5 mg. When used as needed for ED, the usual Cialis dose is 10 mg (with a maximum daily dose of 20 mg). The typical dose of Viagra for ED is 50 mg.

Talk with your doctor to determine whether Cialis or Viagra is the better option for you.

Disclaimer: Healthline 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.