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

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 (reddish skin)
• 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 (in men). Symptoms can include:
  • a painful erection that won’t go away
  • 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
  • a sudden loss or decrease in hearing
  • ringing in the ears
  • dizziness
  • feeling lightheaded or dizzy
  • fainting
  • angina (chest pain

  Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

  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 a man is sexually excited. ED can also prevent a man 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.

  How often should you take tadalafil? Tadalafil should not be taken 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.

  • Heart disease warning. You shouldn’t use 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 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, and vision problems. In men, it can also lead to priapism. These drugs are protease inhibitors and include ritonavir and lopinavir/ritonavir.

  Oral antifungal drugs

  Taking certain antifungal drugs with tadalafil may increase levels of tadalafil in your blood. This can lead to low blood pressure, dizziness and fainting, and vision problems. In men, it can also lead to priapism. 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, and vision problems. In men, it can also lead to priapism. Examples of these drugs include:

  • clarithromycin
  • erythromycin
  • telithromycin

  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 and vardenafil.

  Other pulmonary arterial hypertension (PAH) drugs

  If you take tadalafil with other types of PAH drugs, 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

  Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you’re taking.

  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 develop these symptoms, call 911 or go to the nearest emergency room.

  Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

  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 drop.

  Warnings for people with certain health conditions

  For people with heart disease: Sexual activity creates a risk for your heart. Using tadalafil may increase that risk. Don’t use 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 Peyronie’s disease (a curved or deformed penis).

  For people with vision problems: Retinitis pigmentosa is a rare genetic eye disease. Tadalafil hasn’t been studied in people with this condition, and its use isn’t recommended. 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 for 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 it less often, 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 it 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 women: Studies of this drug in pregnant animals haven’t shown risk to the fetus. However, there aren’t enough studies done in pregnant women using the drug for PAH 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 used in pregnancy if clearly needed.

  For women 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. Talk with your doctor if you’re taking tadalafil and you want to breastfeed.

  For seniors: 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: Children younger than 18 years old shouldn’t use tadalafil. It’s not known if tadalafil is safe and effective in children.

  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

  Dosage for benign prostatic hyperplasia (BPH)

  Generic: Tadalafil

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

  Brand: Cialis

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

  Adult dosage (ages 18–64 years)

  • Typical dosage: 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 finasteride (another drug used to treat BPH), your tadalafil dosage will be 5 mg once daily for up to 26 weeks.

  Child dosage (ages 0–17 years)

  This medication hasn’t been studied in children. It shouldn’t be used in children under age 18 years.

  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.

  Dosage for erectile dysfunction (ED)

  Generic: Tadalafil

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

  Brand: Cialis

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

  Adult dosage (ages 18–64 years)

  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: 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. You may have sexual activity 30 minutes after taking tadalafil and up to 36 hours afterward.

  For once-daily use:

  • Typical starting dosage: 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. You may try to have sexual activity at any time between doses.

  Child dosage (ages 0–17 years)

  This medication hasn’t been studied in children. It shouldn’t be used in children under age 18 years.

  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.

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

  Generic: Tadalafil

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

  Brand: Cialis

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

  Adult dosage (ages 18–64 years)

  • Typical dosage: 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. You may try to have sexual activity at any time between doses. You need to be sexually aroused for tadalafil to help you have an erection.

  Child dosage (ages 0–17 years)

  This medication hasn’t been studied in children. It shouldn’t be used in children under age 18 years.

  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.

  Dosage for pulmonary arterial hypertension (PAH)

  Brand: Adcirca

  • Form: oral tablet
  • Strengths: 20 mg

  Adult dosage (ages 18–64 years)

  • Typical starting dosage: 40 mg (taken as two 20-mg tablets) once per day.
  • When to take your dose: Take this dose at about the same time each day.

  Child dosage (ages 0–17 years)

  This medication hasn’t been studied in children. It shouldn’t be used in children under age 18 years.

  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.

  Special dosage considerations

  • For people with kidney disease: Your body gets rid of tadalafil partly through your kidneys. If your kidneys aren’t working well, more of the drug may stay in your body longer. This raises your risk for side effects. Your doctor may decide to lower your dosage, have you take it less often, or not prescribe it at all for you. This depends on how severe your kidney disease is and whether you are on dialysis.
  • For people with liver disease: Tadalafil is processed by your liver. If your liver isn’t working well, more of the drug may stay in your body longer. This raises your risk for side effects. Your doctor may decide to lower your dosage of tadalafil, have you take it less often, or not prescribe it at all for you. This depends on how severe your liver disease is.

  Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

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

  If you stop or don’t take it on schedule: If you’re being treated for BPH, your BPH symptoms may not improve. These 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: 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 the American Association of Poison Control Centers at 800-222-1222 or through their 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 improve.