What Is Cialis?

Cialis (Tadalafil) is a prescription medication in the PDE5 inhibitor class used to treat erectile dysfunction (ED), benign prostatic hyperplasia (BPH), and pulmonary arterial hypertension (PAH).

Made by Eli Lilly and Company, Cialis was FDA-approved and has become one of the most recognized ED medications worldwide. A generic version — Tadalafil — has been available since 2018, making it much more affordable for most patients. Cialis is not a controlled substance.

Other brand names for Tadalafil include Adcirca (for PAH), Alyq, and Tadliq.

What Is Cialis Used For?

Cialis is FDA-approved for the following conditions:

• Erectile dysfunction (ED) — Helps achieve and maintain an erection sufficient for sexual activity.
• Benign prostatic hyperplasia (BPH) — Treats symptoms of an enlarged prostate, including difficulty urinating, weak stream, and frequent urination.
• Combined ED and BPH — Cialis is the only PDE5 inhibitor FDA-approved to treat both conditions simultaneously.
• Pulmonary arterial hypertension (PAH) — Marketed as Adcirca for this indication. Reduces blood pressure in the lungs and improves exercise capacity.

Tadalafil is also used off-label for Raynaud's phenomenon, lower urinary tract symptoms, and altitude sickness prevention.

To understand how Cialis produces these effects, see our guide on how Cialis works.

How Is Cialis Taken?

Cialis comes as an oral tablet in several strengths:

• 2.5 mg — Daily use
• 5 mg — Daily use (also the standard BPH dose)
• 10 mg — As-needed use
• 20 mg — As-needed use

As-Needed Dosing (for ED)

The typical starting dose is 10 mg taken at least 30 minutes before sexual activity. Your doctor may increase it to 20 mg or decrease it to 5 mg depending on how well it works and how you tolerate it. The key advantage of Cialis over similar medications: it can remain effective for up to 36 hours, earning it the nickname "the weekend pill."

Daily Dosing (for ED or BPH)

For daily use, the dose is 2.5 mg or 5 mg taken at the same time every day, regardless of when you plan sexual activity. Daily dosing provides continuous effectiveness and is the standard approach for treating BPH symptoms.

Important Dosing Rules

• Can be taken with or without food
• Swallow tablets whole — do not crush, break, or split
• Do not take more than one dose per day
• Do not combine with other PDE5 inhibitors like Sildenafil (Viagra) or Vardenafil (Levitra)

Who Should Not Take Cialis?

Cialis is contraindicated (should not be used) in the following situations:

• If you take nitrates — Medications like Nitroglycerin, Isosorbide Dinitrate, Isosorbide Mononitrate, or recreational "poppers" (amyl nitrite). Combining Cialis with nitrates can cause a dangerous, life-threatening drop in blood pressure.
• If you take Riociguat (Adempas) — Used for pulmonary hypertension. Combining it with Cialis can cause severe hypotension.
• If you've had a serious allergic reaction to Tadalafil — Signs include hives, difficulty breathing, or swelling of the face, lips, tongue, or throat.
• If you already take another Tadalafil product — Don't combine Cialis with Adcirca, Alyq, or other Tadalafil brands.

Use caution if you take alpha-blockers (like Tamsulosin or Doxazosin) or blood pressure medications, as Cialis can add to their blood-pressure-lowering effects. For a complete list, see our guide on Cialis drug interactions.

Cialis is not approved for anyone under 18 years of age.

How Much Does Cialis Cost?

Cost varies dramatically depending on whether you use brand-name Cialis or generic Tadalafil:

• Brand-name Cialis: Approximately $400-$960 for 30 tablets, depending on strength.
• Generic Tadalafil (retail without coupon): Can be $300+ for 30 tablets at some pharmacies.
• Generic Tadalafil (with discount coupon): As low as $0.19-$2.00 per pill. For example, a SingleCare coupon brings 90 tablets of 5 mg Tadalafil to about $17 at select pharmacies.

Most insurance plans have limited or no coverage for Cialis, especially for ED. Many insurers impose quantity limits (6-12 tablets per month) or require prior authorization. Generic Tadalafil is more commonly covered, particularly for the daily-use BPH indication. Some plans require step therapy — trying Sildenafil first.

For a complete breakdown of savings strategies, read our guide on how to save money on Cialis.

Final Thoughts

Cialis is a well-established, effective medication for ED and BPH with a unique advantage — up to 36 hours of effectiveness and a convenient daily dosing option. With generic Tadalafil widely available, it's also more affordable than ever.

Talk to your doctor about whether Cialis is right for you, and make sure they know about all medications you're taking — especially nitrates and blood pressure drugs. Once you have a prescription, use Medfinder to find the best price and availability near you.