Cialis Side Effects: What You Need to Know

Cialis (Tadalafil) is one of the most widely prescribed medications for erectile dysfunction (ED) and benign prostatic hyperplasia (BPH). Like all medications, it comes with potential side effects — some minor and temporary, others that need immediate medical attention.

This guide covers the most common and serious side effects of Cialis, based on FDA-approved labeling, so you know exactly what to watch for.

What Is Cialis?

Cialis is a PDE5 inhibitor (phosphodiesterase type 5 inhibitor) made by Eli Lilly and Company. It works by increasing blood flow to certain areas of the body. It's FDA-approved for erectile dysfunction, BPH symptoms, and — under the brand name Adcirca — pulmonary arterial hypertension. A generic version, Tadalafil, has been available since 2018.

For a deeper look at how it works, see our guide on how Cialis works.

Common Side Effects

Most people who take Cialis tolerate it well. The following side effects are the most frequently reported and are usually mild to moderate:

• Headache — The most common side effect. Usually mild and goes away within a few hours.
• Flushing — A feeling of warmth, redness, or a tingly sensation in the face, neck, or chest.
• Nasal congestion — A stuffy or runny nose.
• Upset stomach (dyspepsia) — Indigestion, stomach discomfort, or heartburn.
• Muscle pain (myalgia) — Particularly reported with daily use. Usually occurs 12-24 hours after taking the dose.
• Back pain — Similar to muscle pain, may occur 12-24 hours after dosing. Typically resolves within 48 hours.
• Pain in arms or legs — Less common but reported in clinical trials.
• Dizziness — Mild lightheadedness, especially when standing up quickly.

These side effects are more common at higher doses (20 mg) and often decrease over time as your body adjusts to the medication.

Serious Side Effects

Serious side effects from Cialis are rare but require immediate medical attention. Call your doctor or go to the emergency room right away if you experience any of the following:

• Priapism — An erection that lasts more than 4 hours and is painful. This is a medical emergency. If not treated quickly, priapism can permanently damage the penis.
• Sudden vision loss — This may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION), a rare condition that reduces blood flow to the optic nerve. Stop taking Cialis and seek medical help immediately.
• Sudden hearing loss or ringing in the ears (tinnitus) — May occur with or without dizziness. Stop taking Cialis and contact your doctor.
• Severe drop in blood pressure (hypotension) — Symptoms include fainting, extreme dizziness, or feeling like you might pass out. This is especially dangerous if you take nitrates.
• Heart attack symptoms — Chest pain or pressure, pain spreading to the jaw or shoulder, nausea, sweating. Call 911 immediately.
• Allergic reactions — Hives, difficulty breathing, swelling of the face, lips, tongue, or throat. Seek emergency medical help.

Specific Populations

Older Adults

Cialis does not require dose adjustment based on age alone. However, older adults are more likely to be taking other medications that could interact with Cialis (such as blood pressure drugs or alpha-blockers). Talk to your doctor about all medications you take.

People With Liver Problems

If you have liver impairment, your doctor may limit your dose. The maximum recommended as-needed dose is 10 mg for moderate liver impairment. Daily dosing is not recommended for severe liver impairment.

People With Kidney Problems

For severe kidney impairment (creatinine clearance below 30 mL/min), the maximum as-needed dose is 5 mg once every 72 hours. Daily dosing is not recommended.

People Taking Blood Pressure Medications

Cialis can lower blood pressure. If you're already taking antihypertensives like Amlodipine, Lisinopril, or Metoprolol, the combined effect can cause an excessive drop. Your doctor will monitor this carefully. For more detail, see our guide on Cialis drug interactions.

How to Manage Common Side Effects

If you experience mild side effects, here are some strategies that may help:

• Headache — Over-the-counter pain relief like Acetaminophen (Tylenol) usually helps. Avoid Ibuprofen if you have stomach issues.
• Flushing — Stay cool, avoid alcohol, and drink water. Flushing usually passes within an hour or two.
• Nasal congestion — A saline nasal spray can provide relief. Avoid decongestants that contain Pseudoephedrine without checking with your doctor first.
• Muscle pain and back pain — These are more common with the daily dosing regimen. Gentle stretching, heat, and OTC pain relievers can help. If persistent, your doctor may adjust your dose.
• Upset stomach — Try taking Cialis with a small meal. Avoid heavy, fatty foods and excessive alcohol.
• Dizziness — Stand up slowly from sitting or lying positions. Stay hydrated and avoid alcohol.

If any side effect is persistent, worsening, or interfering with your daily life, talk to your doctor. They may adjust your dose or suggest an alternative. For options, check out our guide on alternatives to Cialis.

Final Thoughts

Most people take Cialis without serious problems. The common side effects — headache, flushing, stuffy nose, muscle aches — are usually mild and temporary. But knowing the serious warning signs (priapism, sudden vision or hearing loss, severe dizziness) can help you act fast if something goes wrong.

Always take Cialis exactly as your doctor prescribes. Never combine it with nitrates or other PDE5 inhibitors. And if something doesn't feel right, don't hesitate to call your doctor.

Need help finding Cialis at a pharmacy near you? Medfinder can help you check stock and compare prices.