Tadalafil (Oral)

Tadalafil is a drug that is used in the treatment of impotence or erectile dysfunction in men. The medication can also be used to successfully treat the symptoms of benign prostatic hyperplasia (BPH). The drug is also used in both sexes to treat pulmonary arterial hypertension.

Overview

Tadalafil is used in the treatment of impotence and erectile dysfunction (ED) in men. This drug can also be used to treat the cause and symptoms of benign prostatic hyperplasia (BPH), enlarged prostate. The medication is also used in both sexes to treat the symptoms of pulmonary arterial hypertension.

In the US, tadalafil is sold under the brand names, Adcirca and Cialis and is dispensed in tablet form. This drug is only available on prescription from your doctor.

In the treatment of ED, the drug works, together with stimulation, by increasing blood flow to the penis, helping the patient to attain and maintain an erection. Tadalafil is one of a category of drugs called phosphodiesterase 5 (PDE5) inhibitors. PDE5s prevent the enzyme, phosphodiesterase type-5 from working too quickly in areas such as the penis. In men who suffer from erectile dysfunction, the penis does not expand and harden when the man becomes sexually excited. In some sufferers, an erection is initially obtained, but the man is unable to maintain it. Under normal circumstances, the man's body increases the flow of blood to his penis, producing an erection. By using PDE5 to control the enzyme, tadalafil can assist in maintaining the erection by increasing blood flow to the member, after the penis is stroked during sexual intercourse. The medication cannot actually cause the erection in the first place.

Benign prostatic hyperplasia (BPH) occurs when the prostate becomes enlarged, causing problems with urination. Patients suffering BPH experience difficulty in beginning urinating, producing a weak urine stream, and feeling the need to urinate very frequently, especially during the night. Tadalafil works to relieve these bothersome symptoms by relaxing smooth muscle tissue in the bladder and prostate and thus relieving pressure on the ureter, effectively reducing the possibility that surgery will be required.

It should be noted that tadalafil does not provide a permanent cure for either erectile dysfunction or benign prostatic hyperplasia. However, it can go a long way towards relieving the symptoms of both these conditions and can be life-changing for many patients.

Tadalafil is also used in both sexes to treat the effects of pulmonary arterial hypertension (high blood pressure). Pulmonary arterial hypertension occurs when the main artery that carries blood from the right side of the heart to the lungs is placed under increased pressure. This happens when the smaller vessels become obstructed, making it harder for the blood to flow easily. In order to maintain an adequate blood flow through the lungs, the heart must work much harder.

Tadalafil works by causing the PDE5 enzyme in the lungs to relax the constricted vessels, increasing the supply of blood to the lungs and relieving the workload of the heart.

Conditions treated

  • erectile dysfunction (ED)
  • benign prostatic hyperplasia (BPH)
  • pulmonary arterial hypertension

Type of medicine

  • tablet
  • phosphodiesterase 5 (PDE5) inhibitor

Side-effects

Together with the many benefits that tadalafil can bring, there are some patients who experience a few unpleasant side-effects. Not everyone suffers unwanted effects when using this medication. However, if you do notice anything unusual after you begin taking your new medication, you should speak to your doctor, as further medical attention could be required.

The following side-effects sometimes affect people taking tadalafil and should always be mentioned to your treating physician straight away:

  • pain in the arm, jaw, neck, or back
  • visual disturbances, including double or blurred vision
  • pains in the chest, tightness, heaviness, or general discomfort
  • flu-like symptoms, chills, cold sweats, sweating
  • confusion
  • feeling faint or dizzy, especially when rising from a chair or bed
  • increased heartbeat
  • headache
  • loss of hearing, pounding in the ears
  • nausea
  • vomiting
  • nervousness
  • breathing difficulties
  • feeling unusually weak or tired
  • pain in the stomach

The following list of side-effects have been reported by people taking tadalafil, although they are not thought to be common:

  • peeling, loosening, cracking, or blistering of the skin
  • diarrhea
  • problems with speech
  • severe, throbbing headache
  • welts, hives, or reddening on the skin
  • red skin lesions, often with a purple, swollen center
  • temporary paralysis of the face, arms, or legs
  • itchy skin
  • pain in the joints or muscles
  • loss of body heat
  • tingling or numbness of the feet, hands, or face
  • irritated or red eyes
  • skin rashes, scaly skin
  • ulcers, sores, or tiny white spots inside the mouth or around the lips
  • cardiac arrest
  • swelling of the lower legs and feet

Some patients have reported a painful or very prolonged erection of the penis.

If you experience any of these effects, you should mention them to your doctor immediately.

The following side-effects are quite common in people taking this medication. These effects will usually resolve naturally as your body becomes acclimatised to your new medication. Ask your doctor for some ideas on how you can prevent or manage these unwanted effects:

  • stomach discomfort, upset, or pain
  • indigestion
  • heartburn
  • belching
  • acid reflux or sour stomach

The side-effects listed below occur less frequently in patients taking tadalafil, but usually resolve themselves after a short time.

  • watering eyes
  • changes in the voice
  • upper abdominal or stomach pain
  • insomnia
  • tender, swollen neck glands
  • swollen joints
  • swelling or puffiness of the eyes or face
  • stomach upset
  • spontaneous erection
  • sleepiness or drowsiness
  • dizziness or a sensation that you are spinning
  • runny nose
  • reduced sensitivity to touch
  • redness, pain, swelling of the eye or eyelid
  • sore throat, hoarseness
  • pain in the arms or legs
  • nasal congestion
  • muscle stiffness, muscle aching, or cramping
  • loose stools
  • fever
  • feeling of warmth, flushed face, neck, arms, and upper chest
  • difficulty swallowing
  • difficulty moving
  • body aches or pain
  • bloody nose
  • changes in color vision

This list of side-effects is not all-inclusive. If you experience any other unusual effects, you should report them to your medical practitioner immediately.

Although very serious allergic reactions to this drug are rare, you should be aware of the symptoms of anaphylaxis. Anaphylaxis is a serious and potentially fatal condition that always demands immediate, emergency medical attention. Symptoms of anaphylaxis include the following:

  • a skin rash
  • itching or swelling sensations, especially of the tongue, face, or throat
  • severe dizziness
  • breathing problems

These symptoms usually occur within a few minutes of the drug being taken. If you begin to experience these signs, call 911 immediately.

Dosage

When you receive prescription for tadalafil, you will be provided with a patient guide. Read the guide thoroughly to make sure that you understand how to use the medication. If you have any questions, ask your doctor or pharmacist for further information.

You must only use this medicine as directed by your treating physician. Do not use more than the dose you have been prescribed. Do not use the medication more often than you have been told to. Do not continue using the medication for longer than you are instructed to by your medical practitioner. Note that using too much of this drug can increase the risk of you suffering unpleasant side-effects.

Tadalafil can be taken with or without food.

Do not crush, split, or break the tablet; swallow it whole.

When used for the treatment of erectile dysfunction, the ability to maintain an erection should show an improvement for up to 36 hours after taking the medication.

The dose of this medicine that you are prescribed will vary between people. Always follow your doctor's orders or those on the dispensary label. The information that follows is just the average for this medication. If the dose you have been prescribed is different, do not change it without first consulting your doctor.

For the treatment of benign prostatic hyperplasia

  • Adults: take 5 mg in one dose, once daily, at the same time.
  • Children: this medication is not recommended for use in children.

If you are currently taking finasteride to treat the symptoms of benign prostate hyperplasia, be sure to ask your doctor for how long you should continue to use both drugs.

For the treatment of erectile dysfunction (as required)

  • Adults: take 10 mg in one dose, once daily, 30 minutes before sexual activity. Your doctor may alter the dose if necessary.
  • Children: this medication is not recommended for use in children.

For the treatment of erectile dysfunction (daily use)

  • Adults: take 2.5 mg in one dose, once daily, at the same time. Your doctor may alter the dose if necessary.
  • Children: this medication is not recommended for use in children.

For the treatment of erectile dysfunction and benign prostatic hyperplasia (daily use)

  • Adults: take 5 mg in one dose, once daily, at the same time. Your doctor may alter the dose if necessary.
  • Children: this medication is not recommended for use in children.

For the treatment of pulmonary arterial hypertension

  • Adults: take 40 mg in one dose, once daily.
  • Children: dose and use as instructed by your doctor.

If you forget your dose of this medication, you should take it as soon as possible. If the time of the next dose is almost due, omit the missed dose and revert to your usual dosage regimen. Do not take double the prescribed dose in an attempt to catch up.

Do not share this medication with anyone else.

If you think that your condition is becoming worse or if you do not notice any improvements in your symptoms, consult your doctor promptly.

If you or someone else in your household has taken an overdose of tadalafil, they may begin to exhibit serious symptoms, such as losing consciousness. They may also complain of breathing difficulties or a shortness of breath. If you think that an overdose has occurred, you should call 911 immediately or contact your local poison control centre.

If you are taking tadalafil once a day for the treatment of erectile dysfunction, or benign prostatic hyperplasia, or for both, you should take it regularly without missing doses in order to gain the best results. Take the medication at the same time each day to make sure that the levels of the drug within your body remain constant.

Major drug interactions

Some drugs should not be used at the same time, because this could affect their efficacy, and it could also increase the risk of you experiencing unpleasant or serious side-effects. However, in some cases, it may be safe to use two or more different medications concurrently, even though an interaction may occur. In these circumstances, your treating physician may suggest adjusting the dose of one of your drugs. Alternatively, your doctor may be able to suggest options for managing the effect of any interactions.

Before you begin using tadalafil, you should compile a list of all the medicines that you are currently using. This list should include prescription and non-prescription drugs, herbal remedies, and vitamin supplements. Give this list to your doctor. Do not alter the dose or frequency of use of any of your prescribed or non-prescription medications, without first consulting your doctor.

If you are already taking an alpha blocker medication to treat an enlarged prostate or hypertension, you may find that also taking tadalafil can cause your blood pressure to become too low. This can lead to dizziness and fainting fits. Your doctor may begin treating you with a lower dose of tadalafil or may decide to alter your alpha blocker medication to mitigate the risk of your blood pressure falling too far.

You should not take this medicine with any other drug that contains tadalafil or another similar medication that is used in the treatment of erectile dysfunction or pulmonary hypertension.

There are a number of medications that may interact with tadalafil. It is not usually advisable to use following medication with tadalafil, although your doctor may elect to do so if appropriate to your treatment:

  • Urapidil
  • Trimazosin
  • Tipranavir
  • Terazosin
  • Telithromycin
  • Telaprevir
  • Tamsulosin
  • Simvastatin
  • Simeprevir
  • Silodosin
  • Saquinavir
  • Ritonavir
  • Riociguat
  • Rifampin
  • Propatyl Nitrate
  • Prazosin
  • Phentolamine
  • Phenoxybenzamine
  • Pentaerythritol Tetranitrate
  • Nitroglycerin
  • Nefazodone
  • Moxisylyte
  • Lopinavir
  • Ketoconazole
  • Itraconazole
  • Isosorbide Mononitrate
  • Isosorbide Dinitrate
  • Indinavir
  • Fosamprenavir
  • Erythromycin
  • Erythrityl Tetranitrate
  • Doxazosin
  • Darunavir
  • Cobicistat
  • Clarithromycin
  • Bunazosin
  • Boceprevir
  • Atazanavir
  • Amyl Nitrite
  • Alfuzosin

Some drugs should not be used when eating certain types of food or using tobacco products or alcohol, as interactions may occur. Check with your doctor if any of these interactions apply when using tadalafil.

Warnings

Although tadalafil is extremely effective and helpful in reducing the symptoms of erectile dysfunction, you should be aware that sexual activity can place extra strain on your heart, especially if you have a history of heart problems. If you have had heart problems and you begin to feel very dizzy, faint, nauseous, or you experience pain in your left arm, chest, and jaw while having sex, you should stop immediately and summon medical assistance as a matter of urgency.

Avoid drinking large amounts of grapefruit juice or taking products containing ethanol while taking tadalafil, as this can exacerbate some side-effects.

While you are taking tadalafil, you must see your doctor for regular progress checks. These check-ups are very important as they allow your treating physician to make sure that your medication is working correctly. You can also use the check-up appointments to discuss any side-effects that you may be experiencing. Your doctor may decide to carry out blood tests to screen you for any unwanted effects that the drug is causing.

Before you begin treatment with tadalafil, you must tell your doctor if you are already taking any other medication, including non-prescription drugs, herbal remedies, or vitamin supplements. You should also inform your doctor if you suffer from allergies to certain food stuffs, food colourings, preservatives, or animal derivatives.

Some medical problems can affect the use of tadalafil. Tell your doctor about any other health conditions you have, especially abnormality of the penis, including birth defects and an odd-shaped or curved penis. There is an increased chance of problems with this medication, and it should be used with caution in these patients.

Tadalafil should not be used in people with the following conditions or a history of them:

  • aged over 50 years
  • coronary artery disease
  • diabetes
  • hyperlipidemia
  • hypertension
  • hypotension
  • eye condition - low cup to disc ratio (‘crowded disc')
  • smoking
  • angina
  • arrhythmia
  • heart attack within the last three months
  • heart failure within the last six months
  • retinal disorders
  • retinitis pigmentosa
  • stroke

Tadalafil should not be used in people who have bleeding disorders or stomach ulcers as there is a chance that problems could be increased.

Tadalafil should be used with extreme caution in people who have blood vessel or heart disease, as there is a chance of low blood pressure occurring.

Tadalafil should be used with extreme caution in people who have kidney or liver disease. The effects of the drug could be increased due to slower removal of the medicine from the body.

Tadalafil should be used with extreme caution in people who are suffering from leukemia, multiple myeloma, or sickle-cell anemia, because the drug can cause issues with prolonged erection of the penis in these cases.

If you've suffered from the serious eye condition NAION you should not take tadalafil as this could increase your chances of suffering from the condition again.

Tadalafil should be used with extreme caution in people who suffer from the lung disease, pulmonary veno-occlusive disease (PVOD), as this drug can make the condition worse.

Note that this drug does not give protection again sexually transmitted infections, including HIV, syphilis, gonorrhea, and hepatitis B. Ask your doctor for advice on ‘safe sex' practices.

In the unlikely event that you develop a painful erection that lasts for more than four hours, you should stop taking tadalafil immediately and summon medical assistance as a matter of urgency. This problem could cause permanent problems if not relieved quickly.

Although this medication is not usually prescribed for women, it may be if your doctor thinks it appropriate. If you think you may be pregnant, inform your doctor before starting a course of this medication. It is not known whether this medication can harm your unborn baby, but you may want to discuss the risks and benefits before you begin using it.

It is not known if this drug can pass into breast milk, but you might want to consider asking your midwife for advice on alternatives for feeding your baby while you are using this medication.

Patients who are taking tadalafil sometimes report spells of dizziness and a spinning sensation. If you begin to feel these effects, do not drive, undertake any activity that requires you to be alert, and do not use machinery. Limit your consumption of alcohol while you are taking this medication. If you find that you are suffering these side-effects, ask your doctor for advice on how best to mitigate them, especially if they are limiting your capacity to work safely.

Storage

You should always keep your supply of tadalafil in a sealed container and at room temperature. Do not refrigerate or freeze the medicine. Avoid exposing the medication to sources of extreme heat or direct sunlight. Do not allow the medication to get wet.

Always keep tadalafil where it cannot be accessed by children or pets. If a pet does eat tadalafil, you should consult your vet immediately.

Do not keep any unused tadalafil. Do not use any medicine that has passed their use-by date. Do not dispose of any unwanted tablets by flushing them down the toilet or drain. Do not discard unused medication with your trash where it could be mistaken for candy by small children.

If you are not sure what to do with left-over medication, ask the advice of your doctor or pharmacist on safe disposal.

Summary

Tadalafil is used in the treatment of impotence and erectile dysfunction (ED) in men. This drug can also be used to treat the symptoms of benign prostatic hyperplasia (BPH), enlarged prostate. The medication is also used in both sexes to treat the symptoms of pulmonary arterial hypertension. Tadalafil is one of a category of drugs called phosphodiesterase 5 (PDE5) inhibitors, and it works in slightly different ways to improve the symptoms of all the aforementioned conditions.

The medication is only available from your doctor on prescription and comes in tablet form. In the US, tadalafil is dispensed under the brand names, Adcirca and Cialis.

Tadalafil can cause a large number of side-effects and it also causes interactions with many commonly used medications. In addition, this medication should not be used with a range of existing medical conditions, including kidney and liver disease, some forms of cancer, high and low blood pressure. Be sure to discuss your existing and historical health conditions in detail with your treating physician before you begin using this drug.

It should be noted that this medication cannot cure the conditions that it is used to treat. However, tadalafil is very effective in controlling the overcoming the troublesome symptoms of erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. However, to make sure that you get the best results from this medication, you will need to work closely with your doctor or specialist. This process will require that you attend your specialist for regular check-ups and blood tests. These tests and discussions are very important in order to make sure that the medication is working properly and to ensure that you are not suffering any unwanted side-effects.

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Last Reviewed:
December 24, 2017
Last Updated:
April 05, 2018