Phosphodiesterase 5 inhibitors

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Phosphodiesterase 5 inhibitors (PDE5Is) are a group of drugs used for the treatment of ED. These drugs relax smooth muscle in the vessels in the penis to increase blood flow. They do not cause an erection without sexual stimulation.

There are 4 approved types of PDE5Is:

  • Sildenafil
  • Tadalafil
  • Vardenafil
  • Avanafil

PDE5Is are the most commonly prescribed treatment for ED. All types of PDE5Is can be equally effective. Which drug is best for you depends on how often you want to have sexual activity, and your personal experience.

Because of the success of PDE5Is in treating ED, there are many fake pills on the market. These drugs are not approved for sale, they may be toxic and may damage your health. Always talk to your doctor or healthcare provider before using or buying medication for ED.

Sildenafil

Sildenafil is the oldest available PDE5I and is available as a pill. It comes in doses of 25, 50, and 100 mg. The dosage can be adjusted according to your needs. You can feel the effects of the drug 30-60 minutes after taking it. They may last for up to 12 hours. If you eat a fatty meal right before taking sildenafil, the drug is less effective.

Interesting Fact

Sildenafil, best known by its brand name Viagra®, is the oldest and best-known drug for ED. Although new drugs have been developed, it still accounts for more than 40% of all PDE5Is sales.

Tadalafil

Tadalafil is available as a pill. It comes in doses of 5, 10, and 20 mg. The dosage can be adjusted according to your needs. You will start to feel the effects of the drug 30 minutes after taking it. It is most effective after 2 hours.

The effects may last for up to 36 hours. In contrast to other PDE5Is, food has no effects on the working of tadalafil. Daily Tadalafil (5 mg) has also been licensed for the treatment of urinary symptoms related to benign prostatic enlargement with or without ED. Your doctor may recommend daily tadalafil if you have ED with BPE.

Vardenafil

Vardenafil is available as a pill, or as a dissolvable tablet. It comes in doses of 5, 10, and 20 mg. The dosage can be adjusted according to your needs. You will start to feel the effects of the drug 30 minutes after taking it. If you eat a fatty meal right before taking vardenafil, the drug is less effective.

Avanafil

Avanafil is the most recent PDE5I to become available. It comes in doses of 50, 100, and 200 mg. The dosage can be adjusted according to your needs. You can feel the effect of the drug 15-30 minutes after taking it. Taking the pill with any food can delay its effects.

Side effects

PDE5Is can cause headaches, flushing of the skin, heartburn, a stuffy nose, and dizziness. Sildenafil and vardenafil can cause changes in vision, and tadalafil and avanafil can cause back and muscle pain. All these side effects stop when you stop taking the pill.

When are PDE5Is not recommended?

The use of PDE5Is is not recommended if you are taking medication with a nitrate basis, or if you take alpha blockers. They could lead to a sudden decrease in blood pressure. If you have any concerns, discuss with your doctor.

What if PDE5Is don’t work?

If you believe that PDE5Is are not working for you, it is important to figure out the cause. For that, you need to answer the following questions:

  • Did you use the medication at least four different times?
  • Have you used the maximum dose of the drug?
  • Have you used the sexual stimulation when you took the drug?
  • Did you wait long enough for the drug to take effect?
  • Did you wait too long before starting sexual stimulation?

If with the highest dose and correct use PDE5Is are still not effective, discuss other possible treatment options with your doctor.