Sildenafil and Tadalafil are drugs used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil and Tadalafil belong to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where this enzyme works.
What is Sildenafil?
Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where this enzyme works.
Erectile dysfunction is a condition where the penis does not harden and expand when a man is sexually excited, or when he cannot keep an erection. When a man is sexually stimulated, his body’s normal response is to increase blood flow to his penis to produce an erection. By controlling the enzyme, sildenafil helps to maintain an erection after the penis is stroked. Without physical action to the penis, such as that occurring during sexual intercourse, sildenafil will not work to cause an erection.
Sildenafil is also used in both men and women to treat the symptoms of pulmonary arterial hypertension. This is a type of high blood pressure that occurs between the heart and the lungs. When hypertension occurs in the lungs, the heart must work harder to pump enough blood through the lungs. Sildenafil works on the PDE5 enzyme in the lungs to relax the blood vessels. This will increase the supply of blood to the lungs and reduce the workload of the heart.
Sildenafil can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking sildenafil, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoked or were over 50 years old. It is not clear whether this medicine is the actual cause of vision loss.
What is Tadalafil?
Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. It is a tablet taken by mouth. Onset is typically within half an hour and the duration is up to 36 hours.
Tadalafil is also used to treat men who have signs and symptoms of benign prostatic hyperplasia (BPH). BPH is caused by an enlarged prostate. Men with BPH usually have difficulty urinating, a decreased flow of urination, hesitation at the beginning of urination, and a need to get up at night to urinate. Tadalafil will make these symptoms less severe and reduce the chance that prostate surgery will be needed. This medicine is also used to treat erectile dysfunction and signs and symptoms of BPH.
Tadalafil is also used in both men and women to treat the symptoms of pulmonary arterial hypertension to improve your ability to exercise. This is high blood pressure that occurs in the main artery that carries blood from the right side of the heart (the ventricle) to the lungs. When the smaller blood vessels in the lungs become more resistant to blood flow, the right ventricle must work harder to pump enough blood through the lungs. Tadalafil works on the PDE5 enzyme in the lungs to relax the blood vessels. This will increase the supply of blood to the lungs and reduce the workload of the heart.
Tadalafil vs Slidenafil: Key Differences
| Points of Comparison | Tadalafil | Sildenafil |
| Prescription required? | Yes | Yes |
| Active ingredient | Tadalafil | Sildenafil |
| Dosage | Available in 2.5, 5, 10 and 20mg tablets | Available in 25, 50 and 100mg tablets |
| Effectiveness | Works for 81 percent of men | Works for 82 percent of men |
| How fast does it work? | Works as quickly as 15-20 minutes. Tadalafil Daily is also available, which works throughout the day | Works within thirty minutes of taking the pill |
| How long does it last? | Effects can last up to 36 hours | Remains active for four to six hours |
| How to take | May be taken with or without food. Be careful to avoid taking with greasy or fatty foods, or eating or drinking grapefruit, as this can affect how the drug works | Best if taken on an empty stomach as food can slow absorption and reduce effectiveness. Be careful to avoid eating or drinking grapefruit, as this can affect how the drug works |
| Selling point | Is available in lower doses and is long- lasting – which means you won’t need to time your sexual activity | Has been around much longer than other treatments, and has a proven track record for safety and success. Generic Sildenafil provides a very cost-effective treatment option |
| Side effects | Facial flushing, headache, indigestion, and a stuffy or runny nose | Facial flushing, headache, indigestion, and a stuffy or runny nose. May also cause a green-blue visual tinge. |