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Erectile Dysfunction (PDE5 Inhibitor)

Drug Class: Commonly Known As: Category:
Adult

Erectile Dysfunction (PDE5 Inhibitor) - What is it for

What is erectile dysfunction (ED)?

    ED is the consistent or recurrent difficulty to achieve or sustain a firm erection or duration for satisfactory sexual intercourse. Many men have dealt with or are dealing with erectile dysfunction.

    Causes of ED include physical trauma, chronic diseases (such as high blood pressure and diabetes), side effects of some medications, excessive alcohol intake, smoking, and psychological factors.

    Various treatment options are available for ED, depending on its causes. This leaflet covers only oral medications named Sildenafil and Tadalafil.

What are Sildenafil and Tadalafil?

    Sildenafil and Tadalafil belong to a class of medications called phosphodiesterase type 5 inhibitors or PDE5 inhibitors. They treat ED by relaxing muscles found in the walls of blood vessels and increasing arterial blood flow at the penis, leading to penile erection.

    An erection will not occur just by taking Sildenafil or Tadalafil. They can help you achieve an erection only if you are sexually stimulated.

Erectile Dysfunction (PDE5 Inhibitor) - Side Effects, Precautions, and Contraindications

What side effects can Erectile Dysfunction (PDE5 Inhibitor) cause?

Side effects common to both Sildenafil and Tadalafil:

  • Headache

Side effects more common with Sildenafil:

  • Flushing – symptoms include a sudden feeling of heat in your face or upper body
  • Abnormal vision – symptoms include a blue tinge to vision, blurred vision, or visual disturbance.

Side effects more common with Tadalafil:

  • Stomach upset; acid reflux
  • Back pain; muscle ache
  • Blocked nose

Most side-effects are transient (goes away over time as the medication wears off), and generally of mild to moderate severity.

If you experience any of the following uncommon or rare but serious side effects, STOP and seek medical help IMMEDIATELY:

  • An allergic reaction
  • Symptoms include rash, hives, itching; swelling of the eyelids, face, lips, tongue or throat; sudden wheezing or difficulty in breathing. 
  • Chest pain
  • If this occurs during intercourse, get in a semi-sitting position to try to relax. Do not use a nitrate to treat your chest pain, as the combination may lead to a dangerous drop in your blood pressure. 
  • Prolonged (lasts for more than 4 hours) and sometimes painful erections
  • Sudden decrease or loss of vision
  • Seizures or fits

If you have any concerns regarding the side effects of Sildenafil or Tadalafil, discuss with your doctor or pharmacist.

Before taking Erectile Dysfunction (PDE5 Inhibitor) , what precautions must I follow?

Inform your healthcare providers if you are:

  • allergic to Sildenafil or Tadalafil.
  • taking medicatios called “nitrates” (e.g. glyceryl trinitrate, isosorbide mononitrate, isosorbide dinitrate) which are used to treat angina (or “chest pain”). Do not take Sildenafil or Tadalafil together with a nitrate, as the combination may lead to a dangerous drop in your blood pressure. If you are on a nitrate (whether long-term or as-needed), discuss with your doctor or pharmacist on whether Sildenafil or Tadalafil is safe for you.
  • are already taking Sildenafil or Tadalafil for other medical conditions.

Also inform your doctor or pharmacist of any other medical conditions that you may have, and of any other long-term medication that you are taking (including supplements, herbal or traditional medication).

What food or medicine must I avoid when I take Erectile Dysfunction (PDE5 Inhibitor) ?

Erectile Dysfunction (PDE5 Inhibitor) - Dosage and How to Use

How should Erectile Dysfunction (PDE5 Inhibitor) be used?

  • If you are taking SILDENAFIL:
    • Take Sildenafil on a when-needed basis, half an hour to one hour (up to 4 hours) before sexual activity.
    • Sildenafil may be taken with or without food; however it may take longer to start working if taken with a high-fat meal.
    • Do not take more than the dose prescribed to you.
    • Do not take Sildenafil more than once a day.
  • If you are taking TADALAFIL on a WHEN-NEEDED basis:
    • Take Tadalafil at least half an hour (up to 36 hours) before sexual activity.
    • Tadalafil may be taken with or without food.
    • Do not take more than the dose prescribed to you.
    • Do not take Tadalafil more than once a day.
    • The recommended dose of Tadalafil when taken as needed is higher than the recommended dose when taken once daily. Avoid taking Tadalafil at when-needed doses continuously every day.
  • If you are taking TADALAFIL on a ONCE-DAILY basis:
    • Take Tadalafil at around the same time of the day, regardless of the timing of sexual activity.
    • Tadalafil may be taken with or without food.
    • If you miss a dose, take the missed dose as soon as you remember. However, if it is time for the next dose, skip the missed dose and take the next dose as scheduled. Do not double your dose to make up for a missed dose.
    • Do not take more than the dose prescribed to you.

What should I do if I miss a dose?

If you are taking TADALAFIL on a ONCE-DAILY basis:

  • If you miss a dose, take the missed dose as soon as you remember. However, if it is time for the next dose, skip the missed dose and take the next dose as scheduled. Do not double your dose to make up for a missed dose.

What should I do if I overdose?

Erectile Dysfunction (PDE5 Inhibitor) - Handling

How should I handle Erectile Dysfunction (PDE5 Inhibitor) safely?

Erectile Dysfunction (PDE5 Inhibitor) - Storage

How should I store Erectile Dysfunction (PDE5 Inhibitor) ?

Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#Store at room temperature;#Store at room temperature (at or below 25-30°C) in the original package, away from sunlight and moist. Keep out of reach of children.

How should I dispose of Erectile Dysfunction (PDE5 Inhibitor) safely?

Erectile Dysfunction (PDE5 Inhibitor) - Additional Information

  • Not all patients may experience benefit from Sildenafil or Tadalafil the first time they take them. Some may take at least 6 tries before they experience benefit. If you experience no benefit from Sildenafil or Taladafil at the prescribed doses after at least 6 tries and while sexually stimulated, speak to your doctor or pharmacist. 
  • In order to get the maximum benefit from Sildenafil or Tadalafil, taking them with excessive amounts of alcohol should be avoided.
  • Smoking cessation, reducing alcohol intake, losing excess weight and increasing physical activity may improve ED. Talk to your doctor or pharmacist for more information.
  • Updated on Sunday, December 18, 2016
  • Article contributed by Pharmacy Singapore General Hospital

The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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