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, 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

How does Cialis work?

Cialis works by enhancing the effects of one of the chemicals the body normally releases into the penis during sexual arousal.

This allows an increase of blood flow into the penis. An erection is the result of an increase in blood flow into certain internal areas of the penis.

  • Cialis is a brand (trade) name for tadalafil which may be used to treat erectile dysfunction (ED) and benign prostatic hyperplasia (BPH).
  • Cialis (tadalafil) works by blocking the action of an enzyme known as cGMP-specific phosphodiesterase type-5 (PDE-5). This enzyme breaks down cGMP, a substance that induces smooth muscles to relax. Blocking PDE-5 means increased levels of cGMP within the smooth muscles which promotes muscle relaxation and vasodilation (a widening of blood vessels).
  • High levels of PDE-5 are found in the penis, lungs, and retina. PDE-5 is also found throughout the body within the smooth muscle cells of blood vessels and muscles.
  • Cialis (tadalafil) belongs to the class of medicines known as PDE-5 inhibitors.

How Common is ED (Erectile Dysfunction)?

Erectile dysfunction (impotence) is the inability to get and keep an erection firm enough for sex.

What is Erectile Dysfunction?

When a man becomes aroused, the brain releases a neurochemical to increase the size of blood vessels carrying blood to the penis and reduce the size of the vessels that carry it out.

Twin compartments that run the length of the penis, called corpora cavernosa, become flush with blood that is trapped in the shaft.

This causes the penis to stiffen and become erect.

If blood flow to the penis is inhibited or the blood vessels are clogged or constricted, erection cannot be achieved or maintained.

This is one of the primary causes of erectile dysfunction.

Having erection trouble from time to time isn’t necessarily a cause for concern. If erectile dysfunction is an ongoing issue, however, it can cause stress, affect your self-confidence and contribute to relationship problems. Problems getting or keeping an erection can also be a sign of an underlying health condition that needs treatment and a risk factor for heart disease.

If you’re concerned about erectile dysfunction, talk to your doctor — even if you’re embarrassed. Sometimes, treating an underlying condition is enough to reverse erectile dysfunction. In other cases, medications or other direct treatments might be needed.

Symptoms of Erectile Dysfunction

Symptoms of ED can include:

  • Erections are hard to get
  • Erections are less rigid
  • Erections are not satisfactory for penetration
  • Erections cannot be maintained during sexual activity or until the man’s orgasm is reached
  • Erections cannot be achieved at all

Men with ED can lose confidence in their sexual ability and their overall sense of self-worth can be negatively affected.

Erectile dysfunction can have a devastating psychological impact for individuals and couples.

Causes of Erectile Dysfunction

In the majority of cases, erectile dysfunction occurs when blood flow to the penis is inhibited either by cardiovascular problems or poor nerve signalling. Healthy arousal engorges the penile tubes (corpora cavernosum) with arterial blood causing it to stiffen and become erect. The engorged corpora occlude the venous outflow of blood, creating a rigid or full erection. Erection dysfunction occurs when there is either poor influx of arterial blood or efflux of venous blood (venous leak).

While both psychological and biological factors can cause erectile dysfunction, in reality the mind and body work together in sexual arousal, so most men have both factors in varying proportions.

Psychological Causes of ED
Men who suffer from clinical depression, anxiety, chronic stress, or who are experiencing challenges in their relationship with their partner, may have erectile difficulties. Some of the medications that treat depression can also contribute to the problem. The inability to perform sexually can cause further anxiety and depression, creating a downward spiral.

Biological Causes of ED
Health conditions or lifestyle choices that affect blood circulation, structural anomalies in the penis, certain neurological conditions, hormonal deficiencies, and medication side effects, can all contribute to erectile dysfunction. The chart below lays out examples of potential biological reasons for a man’s erectile dysfunction.

Risk factors

As you get older, erections might take longer to develop and might not be as firm. You might need more direct touch to your penis to get and keep an erection.

Various risk factors can contribute to erectile dysfunction, including:

  • Medical conditions, particularly diabetes or heart conditions
  • Tobacco use, which restricts blood flow to veins and arteries, can — over time — cause chronic health conditions that lead to erectile dysfunction
  • Being overweight, especially if you’re obese
  • Certain medical treatments, such as prostate surgery or radiation treatment for cancer
  • Injuries, particularly if they damage the nerves or arteries that control erections
  • Medications, including antidepressants, antihistamines and medications to treat high blood pressure, pain or prostate conditions
  • Psychological conditions, such as stress, anxiety or depression
  • Drug and alcohol use, especially if you’re a long-term drug user or heavy drinker

Complications

Complications resulting from erectile dysfunction can include:

  • An unsatisfactory sex life
  • Stress or anxiety
  • Embarrassment or low self-esteem
  • Relationship problems
  • The inability to get your partner pregnant

Prevention of ED

The best way to prevent erectile dysfunction is to make healthy lifestyle choices and to manage any existing health conditions. For example:

    • Work with your doctor to manage diabetes, heart disease or other chronic health conditions.
    • See your doctor for regular checkups and medical screening tests.
    • Stop smoking, limit or avoid alcohol, and don’t use illegal drugs.
    • Exercise regularly.
    • Take steps to reduce stress.
    • Get help for anxiety, depression or other mental health concerns.

Diagnosis of ED

Finding the cause of your ED will help direct your treatment options.

Diagnosing ED starts with your health care provider asking questions about your heart and vascular health and your erection problem. Your provider may also give you a physical exam, order lab tests or refer you to a Urologist.

Health and ED History

Your doctor will ask you questions about your health history and lifestyle. It is of great value to share facts about drugs you take, or if you smoke or how much alcohol you drink. He/she will ask about recent stressors in your life. Speak openly with your doctor, so he/she can help you find the best choices for treatment

What Questions Will the Health Care Provider Ask?

Questions about your health:
      • What prescription drugs, over-the-counter drugs or supplements do you take?
      • Do you use recreational drugs?
      • Do you smoke?
      • How much alcohol do you drink?
      • Have you had surgery or radiation therapy in the pelvic area?
      • Do you have any urinary problems?
      • Do you have other health problems (treated or untreated)?

Questions About ED

Knowing about your history of ED will help your health provider learn if your problems are because of your desire for sex, erection function, ejaculation, or orgasm (climax). Some of these questions may seem private or even embarrassing. However, be assured that your doctor is a professional and your honest answers will help find the cause and best treatment for you.

Questions about your ED symptoms:

    • How long have you had these symptoms? Did they start slowly or all at once?
    • Do you wake up in the morning or during the night with an erection?
    • If you do have erections, how firm are they? Is penetration difficult?
    • Do your erections change at different times, like when going in a partner, during stimulation by mouth, or with masturbation?
    • Do you have problems with sex drive or arousal?
    • Do you have problems with ejaculation or orgasm (climax)?
    • How is this problem changing the way you enjoy sex?
    • Do you have painful with erections, feel a lump or bump in the penis or have penile curvature? These are signs of Peyronie’s Disease which can be treated but calls for an expert in urology to assess and manage.

Questions About Stress and Emotional Health

Your health care provider may ask you questions about depression or anxiety. He or she may ask about problems in your relationship with a partner. Some health care providers may also ask if they may talk to your sex partner.

    • Are you often under a lot of stress, or has something recently upset you?
    • Do you have any anxiety, depression or other mental health issues?
    • Are you taking any drugs for your mental health?
    • How satisfied are you with your sex life? Has there been any changes lately?
    • How is your relationship with your partner? Has there been any changes lately?

Physical Exam

A physical exam checks your total health. Examination focusing on your genitals (penis and testicles) is often done to check for ED. Based on your age and risk factors, the exam may also focus on your heart and blood system: heart, peripheral pulses and blood pressure. Based on your age and family history your doctor may do a rectal exam to check the prostate. These tests are not painful. Most patients do not need a lot of testing before starting treatment.

Lab Tests

Your health care provider may order blood tests and collect a urine sample to look for health problems that cause ED.

Other Tests

Questionnaires are often used by health experts to rate your ability to initiate and keep erections, gauge your satisfaction with sex and help identify any problems with orgasm.

Advanced Erectile Function Tests

For some men with ED, specialized testing may be needed to guide treatment or re-assess you after a treatment fails.

    • Blood work to check Testosterone and other male hormones
    • Blood work to measure blood sugar (Diabetes)
    • Ultrasonography (penile Doppler) to check blood flow
    • A shot into the penis with a vascular stimulant to cause an erection
    • Pelvic x-rays like arteriography, MRI or CT scanning are rarely needed to check ED unless there is history of trauma or cancer
    • Nocturnal penile tumescence (NPT), an overnight test to check for sleep erection

Treatment of ED

The treatment for ED starts with taking care of your heart and vascular health. Your doctor may point out ‘risk factors’ that can be changed or improved.

You may be asked to change certain food habits, stop smoking, increase workouts or stop using drugs or alcohol. You may be offered alternatives to the drugs you take. (Never stop or change prescription drugs without first talking to your health care provider.)

Your health care provider may also suggest treating emotional problems. These could stem from relationship conflicts, life’s stressors, depression or anxiety from past problems with ED (performance anxiety).
The treatments below are available to treat ED directly.

Non-invasive treatments are often tried first. Most of the best-known treatments for ED work well and are safe. Still, it helps to ask your health care provider about side effects that could result from each option:

  • Oral drugs or pills known as phosphodiesterase type-5 inhibitors are most often prescribed in the U.S. for ED (Viagra, Cialis, Levitra, Stendra)
  • Testosterone Therapy (when low testosterone is detected in blood testing)
  • Penile Injections (ICI, intracavernosal Alprostadil)
  • Intraurethral medication (IU, Alprostadil)
  • Vacuum Erection Devices
  • Penile Implants
  • Surgery to bypass penile artery damage for some younger men with a history of severe pelvic trauma. Penile vascular surgery is not recommended for older men with hardened arteries.

Oral Drugs (PDE5 inhibitors)

Drugs known as PDE type-5 inhibitors increase penile blood flow. These are the only oral agents approved in the U.S. by the Food and Drug Administration for the treatment of ED.

    • Viagra ® (sildenafil citrate)
    • Levitra ® (vardenafil HCl)
    • Cialis ® (tadalafil)
    • Stendra ® (avanafil)

For best results, men with ED take these pills about an hour or two before having sex. The drugs require normal nerve function to the penis. PDE5 inhibitors improve on normal erectile responses helping blood flow into the penis. Use these drugs as directed. About 7 out of 10 men do well and have better erections. Response rates are lower for Diabetics and cancer patients.

If you are taking nitrates for your heart, you SHOULD NOT take any PDE5 inhibitors. Always speak with your health care provider before using a PDE5 inhibitor to learn how it might affect your health.

Most often, the side effects of PDE5 inhibitors are mild and often last just a short time. The most common side effects are:

    • Headache
    • Stuffy nose
    • Facial flushing
    • Muscle aches
    • Indigestion

In rare cases, the drug Viagra ® can cause blue-green shading to vision that lasts for a short time. In rare cases, the drug Cialis ® can cause or increase back pain or aching muscles in the back. In most cases, the side effects are linked to PDE5 inhibitor effects on other tissues in the body, meaning they are working to increase blood flow to your penis and at the same time impacting other vascular tissues in your body. These are not ‘allergic reactions’.

Testosterone Therapy

In those rare cases where a low sex drive and low blood levels of Testosterone are at fault for ED, Testosterone Therapy may fix normal erections or help when combined with ED drugs (PDE type 5 inhibitors).

Vacuum Erection Device

A vacuum erection device is a plastic tube that slips over the penis, making a seal with the skin of the body. A pump at the other end of the tube makes a low-pressure vacuum around the erectile tissue, which results in an erection. An elastic ring is then slipped onto the base of the penis. This holds the blood in the penis (and keeps it hard) for up to 30 minutes. With proper training, 75 out of 100 men can get a working erection using a vacuum erection device.

Intracavernosal (ICI) and Urethra (IU) Therapies

If oral drugs don’t work, the drug Alprostadil is approved for use in men with ED. This drug comes in two forms, based on how it is to be used: intracavernosal injection (called “ICI”) or through the urethra (called “IU therapy”).

 

Self-Injection Therapy

Alprostadil is injected into the side of penis with a very fine needle. It’s of great value to have the first shot in the doctor’s office before doing this on your own. Self-injection lessons should be given in your doctor’s office by an experienced professional. The success rate for getting an erection firm enough to have sex is as high as 85% with this treatment. Many men who do not respond to oral PDE5 inhibitors can be ‘rescued’ with ICI.

ICI Alprostadil may be used as a mixture with two other drugs to treat ED. This combination therapy called “bimix or trimix” is stronger than alprostadil alone and has become standard treatment for ED. Only the Alprostadil ingredient is FDA approved for ED. The amount of each drug used can be changed based on the severity of your ED, by an experienced health professional. You will be trained by your health professional on how to inject, how much to inject and how to safely raise the drug’s dosage if necessary.

ICI therapy often produces a reliable erection, which comes down after 20-30 minutes or with climax. Since the ICI erection is not regulated by your penile nerves, you should not be surprised if the erection lasts after orgasm. The most common side effect of ICI therapy is a prolonged erection. Prolonged erections (>1 hour) can be reversed by a second injection (antidote) in the office.

Men who have penile erections lasting longer than two to four hours should seek Emergency Room care. Priapism is a prolonged erection, lasting longer than four hours. It is very painful. Failure to undo priapism will lead to permanent penile damage and untreatable ED.

Intraurethral (IU) Therapy

For IU therapy, a tiny medicated pellet of the drug, Alprostadil, is placed in the urethra (the tube that carries urine out of your body). Using the drug this way means you don’t have to give yourself a shot, unfortunately it may not work as well as ICI. Like ICI therapy, IU Alprostadil should be tested in the office, before home usage.

The most common side effects of IU alprostadil are a burning feeling in the penis. If an erection lasts for over four hours, it will need medical attention to make it go down.

Surgical Treatment

The main surgical treatment of ED involves insertion of a penile implant (also called penile prostheses). Because penile vascular surgery is not recommended for aging males who have failed oral PDE5 inhibitors, ICI or IU therapies, implants are the next step for these patients. Although placement of a penile implant is a surgery which carries risks, they have the highest rates of success and satisfaction among ED treatment options.

Penile implants are devices that are placed fully inside your body. They make a stiff penis that lets you have normal sex. This is an excellent choice to improve uninterupted intimacy and makes relations more spontaneous.

There are two types of penile implants.

Semi rigid Implant (Bendable)

The simplest kind of implant is made from two easy-to-bend rods that are most often made of silicone. These silicone rods give the man’s penis the firmness needed for sexual penetration. The implant can be bent downward for peeing or upward for sex.

Inflatable Implant

With an inflatable implant , fluid-filled cylinders are placed lengthwise in the penis. Tubing joins these cylinders to a pump placed inside the scrotum (between the testicles). When the pump is engaged, pressure in the cylinders inflate the penis and makes it stiff. Inflatable implants make a normal looking erection and are natural feeling for your partner. Your surgeon may suggest a lubricant for your partner. With the implant, men can control firmness and, sometimes, the size of the erection. Implants allows a couple to be spontaneously intimate. There is generally no change to a man’s feeling or orgasm.