Tadalafil (Oral Tablet): Side Effects, Dosage, and Review

Highlights for tadalafil

• Tadalafil oral tablet is available as a generic drug and as brand-name drugs. Brand names: Cialis, Adcirca.
• Tadalafil comes only as a tablet you take by mouth.
• Tadalafil is used to treat the symptoms of benign prostatic hyperplasia (BPH) and erectile dysfunction (ED). Tadalafil is also used to treat pulmonary arterial hypertension (PAH).

What is tadalafil?

Tadalafil is a prescription drug. It comes as an oral tablet.

Tadalafil oral tablet is available as the brand-name drugs Cialis and Adcirca. It’s also available in a generic form. Generic drugs usually cost less than the brand-name version. In some cases, they may not be available in all strengths or forms as the brand-name drug.

Why it’s used

Tadalafil (Cialis) is used for treatment of benign prostatic hyperplasia (BPH) or erectile dysfunction (ED), or both conditions. Tadalafil (Adcirca) is used to treat pulmonary arterial hypertension (PAH).

With BPH, the prostate gland is enlarged but isn’t cancerous. It can pinch or squeeze your urethra (the tube that carries urine from the kidneys out of the body). Symptoms of BPH include trouble urinating, painful urination, and a frequent or urgent need to urinate.

With ED, the penis doesn’t fill up with enough blood to harden and expand when you’re sexually excited. ED can also prevent you from keeping an erection.

PAH is a rare but serious form of high blood pressure. It occurs in the pulmonary arteries, which are blood vessels in your lungs.

How tadalafil is used

How long before sex should you take tadalafil? Tadalafil can be prescribed in two different ways, either a daily dosage or on an as-needed basis. Your doctor will prescribe either one. If you’re taking tadalafil on an as-needed basis, you should take it at least 30 minutes before sex. If you’re taking it daily, try to take it around the same time every day. It takes about 30 minutes for tadalafil’s effects to kick in after you take a dose.

How often should you take tadalafil? You should not take tadalafil more than once in a 24-hour period. If you miss a dose during this period, take the missed dose as soon as possible. However, never double your dosages. If you miss a dose and you’re already due for the next one, skip the missed dose.

Should tadalafil be taken with food? Tadalafil can be taken with or without food and is not affected by the type of food you take with it.

How it works

Tadalafil belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Tadalafil may help relax the muscle in your prostate and bladder. This could help improve your BPH symptoms.

To improve ED symptoms, tadalafil helps increase blood flow to the penis. This can help you get and keep an erection. For tadalafil to help you have an erection, you need to be sexually aroused.

For PAH, tadalafil works to improve your ability to exercise by relaxing blood vessels in your lungs. This increases blood flow.

Tadalafil side effects

Tadalafil oral tablet doesn’t usually cause drowsiness, but it can cause other side effects.

More common side effects

The more common side effects that can occur with tadalafil include:

• headache
• upset stomach
• back pain
• muscle aches
• flushing
• stuffy or runny nose
• diarrhea

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

• Priapism. Symptoms can include:
  • a painful erection that won’t go away
• Vision changes. Symptoms can include:
  • seeing a shade of blue when looking at objects
  • trouble telling the difference between the colors blue and green
  • a sudden decrease or loss of vision in one or both eyes
• Hearing loss. Symptoms can include:
  • a sudden loss or decrease in hearing
  • ringing in the ears
  • dizziness
• Low blood pressure. Symptoms can include:
  • feeling lightheaded or dizzy
  • fainting
  • angina (chest pain)

Important warnings

• Heart disease warning. Your doctor won’t prescribe tadalafil if you have a heart condition and your doctor has advised against sexual activity. Call your doctor right away if you have symptoms during sex such as chest pain, dizziness, or nausea. Sexual activity can put an extra strain on your heart. This is especially true if your heart is already weak from a heart attack or heart disease.
• Priapism warning. Priapism is an erection that won’t go away. Without treatment, this condition could cause permanent damage to your penis. This damage includes impotence (not being able to have an erection). If you get an erection that lasts more than 4 hours, call your doctor right away.

Tadalafil may interact with other medications

Tadalafil oral tablets can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk with your doctor or pharmacist.

Examples of drugs that can cause interactions with tadalafil are listed below.

Angina drugs (nitrates)

If you take tadalafil with nitrates, your blood pressure could suddenly drop to dangerously low levels. This could make you dizzy or cause you to faint. Examples of nitrates include:

• nitroglycerin
• isosorbide dinitrate
• isosorbide mononitrate
• amyl nitrite
• butyl nitrite

High blood pressure or prostate drugs (alpha-blockers)

If you take tadalafil with certain alpha-blockers, your blood pressure could suddenly drop to low levels that are dangerous. This could make you dizzy or cause you to faint. Examples of these drugs include:

• terazosin
• tamsulosin
• doxazosin
• prazosin
• alfuzosin

Certain HIV drugs

Taking tadalafil with certain HIV drugs could increase tadalafil levels in your blood. This can lead to low blood pressure, dizziness and fainting, priapism, and vision problems. These drugs are protease inhibitors and include ritonavir and lopinavir/ritonavir.

Oral antifungal drugs

Taking certain oral antifungal drugs with tadalafil may increase levels of tadalafil in your blood. This can lead to low blood pressure, dizziness and fainting, priapism, and vision problems. Examples of these drugs include ketoconazole and itraconazole.

Antibiotics

Taking certain antibiotics with tadalafil may raise the level of tadalafil in your blood. This can lead to low blood pressure, dizziness and fainting, priapism, and vision problems. Examples of these drugs include:

• clarithromycin
• erythromycin

Other types of antibiotics may lower the level of tadalafil in your blood. This could prevent tadalafil from working well. This includes drugs such as rifampin.

Other erectile dysfunction (ED) drugs

These medications work in the same way as tadalafil. If you take them with tadalafil, it increases your risk for side effects. Examples of these drugs include sildenafil (Viagra, Revatio) and vardenafil (Levitra).

Other pulmonary arterial hypertension (PAH) drugs

If you take tadalafil with other types of PAH drugs, such as riociguat (Adempas), your blood pressure could suddenly drop to dangerously low levels. The drug riociguat is in this drug class.

Stomach acid drugs

Taking these medications with tadalafil may keep your body from absorbing tadalafil well. An example of this type of drug is magnesium hydroxide/aluminum hydroxide.

Epilepsy drugs

Taking certain anti-seizure drugs with tadalafil may lower the level of tadalafil in your blood. This could prevent tadalafil from working well. Examples of these drugs include:

• carbamazepine
• phenytoin
• phenobarbital

Tadalafil warnings

This drug comes with several warnings.

Allergy warning

Tadalafil can cause a severe allergic reaction. Symptoms can include:

• rash
• hives
• trouble breathing or swallowing
• swelling of your lips, throat, or tongue

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should keep taking tadalafil.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to tadalafil, they may have you switch to a different treatment.

Grapefruit interaction warning

Eating grapefruit or drinking grapefruit juice may increase the levels of tadalafil in your blood. This raises your risk for side effects.

Alcohol interaction warning

Don’t drink large amounts of alcohol when taking tadalafil. Both alcohol and tadalafil can dilate (widen) your blood vessels. When used together, they can cause your blood pressure to decrease, which can be dangerous.

Warnings for people with certain health conditions

For people with heart disease: Sexual activity creates a risk for your heart. Taking tadalafil may increase that risk. Your doctor won’t prescribe tadalafil if you have a heart condition and your doctor has advised against sexual activity.

For people at risk for prolonged erections: Tadalafil may cause priapism. This condition causes a painful, long-lasting erection. It is a medical emergency. Talk with your doctor before using tadalafil if you have a condition that puts you at higher risk for priapism. These conditions include blood cell conditions such as sickle cell anemia, multiple myeloma, or leukemia, as well as Peyronie’s disease.

For people with vision problems: Tadalafil hasn’t been studied in people with retinitis pigmentosa (a rare genetic eye disease), and your doctor won’t prescribe tadalafil if you have a history of this condition. Also, tell your doctor if you’ve ever had severe vision loss, including a condition called NAION (non-arteritic anterior ischemic optic neuropathy). If you’ve had NAION and take tadalafil, you may be at increased risk of having NAION again.

For people with kidney disease or on dialysis: Your body may not be able to get rid of tadalafil correctly. This means the drug would stay in your body longer and raise your risk for side effects. Your doctor may start you on a lower dosage, have you take tadalafil less often than usual, or not prescribe it at all.

For people with liver problems: Your body may not process tadalafil correctly. This means the drug would stay in your body longer and raise your risk for side effects. Your doctor may start you on a lower dosage, have you take tadalafil less often, or not prescribe it at all.

For people with bleeding disorders or peptic ulcers: Tadalafil hasn’t been studied in people with these conditions. Using tadalafil may cause or worsen bleeding or ulcers. If you take tadalafil, your doctor may monitor you more closely.

Warnings for other groups

For pregnant people: Tadalafil is prescribed for males, so it’s unlikely to be taken during pregnancy.

Studies of this drug in pregnant animals haven’t shown risk to the fetus. However, there aren’t enough studies to show whether the drug poses a risk to a human fetus.

Talk with your doctor if you’re pregnant or planning to become pregnant. Animal studies don’t always predict the way humans would respond. Therefore, this drug should only be taken during pregnancy if clearly needed.

Note: In this article, we use the term “male” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

For people who are breastfeeding: It isn’t known if tadalafil passes into breast milk. If it does, it may cause serious effects in a child who is breastfed. Tadalafil is prescribed for males, so it’s unlikely to be taken while breastfeeding. But talk with your doctor if you’re taking tadalafil and you want to breastfeed.

For older adults: If you are age 65 years or older, your body may process this drug more slowly. Your doctor may start you on a lower dosage so that tadalafil doesn’t build up too much in your body. High levels of the drug in your body can be dangerous.

For children: Doctors don’t prescribe tadalafil for use in children younger than 18 years old. It’s not known if tadalafil is safe and effective in children.

Tadalafil dosage

All possible dosages may not be included here. Your doctor will tell you what dosage is right for you. Your dosage, drug form, and how often you take the drug will depend on:

• your age
• the condition being treated
• how severe your condition is
• other medical conditions you have
• how you react to the first dose

Drug form and strengths

Generic: Tadalafil

• Form: oral tablet
• Strengths: 2.5 milligrams (mg), 5 mg, 10 mg, and 20 mg

Brand: Cialis

• Form: oral tablet
• Strengths: 2.5 mg, 5 mg, 10 mg, and 20 mg

Brand: Adcirca

• Form: oral tablet
• Strengths: 20 mg

Dosage for benign prostatic hyperplasia (BPH)

• Typical dosage for BPH: One 5-mg tablet per day.
• When to take your dose: Take it at about the same time each day. Don’t take tadalafil more than once per day.
• When using with other drugs: If you’re taking tadalafil with another BPH drug called finasteride (Propecia, Proscar), your tadalafil dosage will be 5 mg once daily for up to 26 weeks.

Dosage for erectile dysfunction (ED)

For ED, tadalafil can be used either as needed or taken once a day. Don’t take tadalafil more than once per day.

For as-needed use:

• Typical starting dosage for ED as needed: 10 mg.
• Dosage increases: Your doctor may increase your dose to 20 mg or decrease it to 5 mg. This depends on how tadalafil is working for you and how well your body reacts to it.
• When to take your dose: Take one tadalafil tablet before you expect to have sexual activity. The drug’s effects start about 30 minutes after taking tadalafil and last for up to 36 hours.

For once-daily use:

• Typical starting dosage for ED once daily: 2.5 mg per day.
• Dosage increases: Your doctor may increase your dose to 5 mg per day, depending on how well tadalafil is working for you and how well your body reacts to it.
• When to take your dose: Take one tadalafil tablet every day. Take it at about the same time each day. The drug’s effects start about 30 minutes after taking tadalafil and last for up to 36 hours.

Dosage for erectile dysfunction and benign prostatic hyperplasia (ED/BPH)

• Typical dosage for ED/BPH: One 5-mg tablet every day.
• When to take your dose: Take this drug at about the same time each day. Don’t take tadalafil more than once per day. The drug’s effects start about 30 minutes after taking your dose and last for up to 36 hours. You need to be sexually aroused for tadalafil to help you have an erection.

Dosage for pulmonary arterial hypertension (PAH)

• Typical starting dosage for PAH: 40 mg (taken as two 20-mg tablets) once per day.
• When to take your dose: Take your dose at about the same time each day. You should take your dose all at once (don’t split into two doses per day.)

Special dosage considerations

• Senior dosage (ages 65 years and older): Your body processes this drug more slowly. Your doctor may start you on a lowered dosage to keep the drug from building up too much in your body. Too much of the drug in your body can be dangerous.
• For people with kidney or liver problems: Your body processes tadalafil in your liver and gets rid of tadalafil partly through your kidneys. If your kidneys or liver aren’t working well, more of the drug may stay in your body longer. This raises your risk for side effects. Your doctor may lower your dosage, have you take tadalafil less often, or not prescribe it at all for you. This may depend on how severe your condition is and whether you are on dialysis.

Take as directed

Tadalafil oral tablet is used for long-term treatment. It comes with risks if you don’t take it as prescribed.

If you stop taking tadalafil or don’t take it on schedule: If you’re being treated for BPH, your BPH symptoms may not reduce. These symptoms may include trouble starting to urinate, straining while trying to urinate, and a weak urine flow. They may also include frequent urges to urinate.

If you’re being treated for ED, you may not be able to get and keep an erection during sexual activity.

If you’re being treated for PAH, it won’t help you feel better. It won’t decrease your symptoms, such as shortness of breath during physical activity.

If you take too much tadalafil: You will be at an increased risk for side effects.

If you think you’ve taken too much of this drug, call your doctor or seek guidance from America’s Poison Centers at 800-222-1222 or through its online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: Take it when you remember, but don’t take more than one dose per day. Never try to catch up by taking two doses at once. This could cause dangerous side effects.

How to tell if the drug is working: Your symptoms of BPH, ED, or PAH should reduce.

Tadalafil cost and coupons

Whether you have health insurance or not, cost may be a factor when you’re considering tadalafil. What you’ll pay for tadalafil tablets may depend on several things, such as your treatment plan and the pharmacy you use.

Here are a few things to consider regarding cost:

• Cost information and savings coupons: You can visit Optum Perks to get price estimates of what you’d pay for tadalafil when using coupons from the site. See the coupon options below. (Note: Optum Perks coupons cannot be used with any insurance copays or benefits.)
• Savings programs: Some websites provide details about drug assistance programs, ways to make the most of your insurance coverage, and links to savings cards and other services. Two such websites are:
  • Medicine Assistance Tool
  • NeedyMeds

You can refer to this tadalafil cost article for more details. And, you can learn more about saving on your prescriptions.

Important considerations for taking tadalafil

Keep these considerations in mind if your doctor prescribes tadalafil for you.

General

• If your doctor told you to take tadalafil once daily, you should take it every day at about the same time.
• Don’t cut your tadalafil tablets. You should take the entire dose.

Storage

• Store tadalafil at room temperature between 59°F and 86°F (15°C and 30°C).
• Keep this drug away from high temperatures.
• Don’t store this medication in moist or damp areas, such as bathrooms.

Travel

When traveling with your medication:

• Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
• Don’t worry about airport X-ray machines. They can’t harm your medication.
• You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.
• Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

Clinical monitoring

Before prescribing tadalafil, your doctor may do blood tests. These tests will check how well your liver and kidneys are working. If your test results aren’t normal or if you have liver or kidney disease, your doctor may change your prescription. Your doctor may start you on a lower dosage of tadalafil, have you take it less often, or not prescribe it at all for you.

If you’re taking tadalafil for BPH, your doctor may perform an exam and do a blood test called a prostate-specific antigen (PSA) test. This is because the symptoms of BPH and prostate cancer can be similar. These tests will help make sure you don’t have prostate cancer before you start taking tadalafil.

Prior authorization

Many insurance companies require a prior authorization for this drug. This means your doctor will need to get approval from your insurance company before your insurance company will pay for the prescription.

Frequently asked questions about tadalafil

How long does tadalafil last? Tadalafil can last within the body for 36 hours. It’s important to not take tadalafil more often than your doctor prescribes. If you take tadalafil as needed for ED, you should avoid taking more than one tablet in a 24-hour time frame. It’s also important to note that in order to see the effects of the tablet for ED, you must be sexually aroused.

Does tadalafil lower blood pressure? Tadalafil works by opening up blood vessels in the body, which makes it easier for blood to flow. For this reason, the drug may help lower blood pressure.

Is tadalafil stronger than Viagra? Tadalafil and Viagra both work to treat ED, and the main difference between the two is how long tadalafil lasts in comparison to tadalafil. Tadalafil can last for up to 36 hours in the body, while Viagra can last up to 5 hours.