Treatment for erectile dysfunction (ED) is often expensive. That’s why it’s important to offer patients options and medication alternatives within their treatment plans. Among the most commonly prescribed of those options are Tadalafil and Sildenafil.

More than just ED: Tadalafil & Sildenafil

Tadalafil (a generic medication for Cialis®) and Sildenafil (a generic medication for Viagra®), are best-known for treating erectile dysfunction, but they are also indicated for the treatment of pulmonary arterial hypertension, enlarged prostate, and various other medical conditions. They are among the four major medications known as “PDE-5 Inhibitors” that are predominately used to treat ED.

Therapeutic Mechanism

While neither Tadalafil or Sildenafil will automatically cause an erection, they help increase blood flow to the genitals to aid in achieving and maintaining an erection. This increase in blood flow is a result of the medications blocking the enzyme PDE-5 from decomposing a compound called cGMP. The accumulation of cGMP is what relaxes the smooth muscles that are found in the penis. This relaxation allows blood to flow in more easily, leading to an erection.

What’s the difference between them?

Tadalafil or Sildenafil offer similar patient efficacy and safety. However, some studies show that patients experience different side effects and may prefer one medication over the other.1

Sildenafil must generally be taken on an empty stomach or with a minimal amount of low-fat food to help the body better absorb the medicine, while Taldalfil can be taken with or without food.

Another difference to note is that Tadalafil begins working within 30-60 minutes of ingestion and can remain active up to 36 hours, where Sildenafil only remains active up to 6 hours.

Which should be prescribed?

Since Tadalafil stays in the body longer, it is important to note if patients are on other prescription medications. In that case, Sildenafil may be a better option so there is a lessened likelihood for medication interactions. It’s also dependent on that patient’s sexual activity. If they are more inclined to plan out moments of intimacy, Sildenafil may be a better option. If they are more inclined to be spontaneous, Tadalafil may be a better choice since it lasts longer in the system.

Ultimately, it is the physician’s responsibility to determine the best option for each patient on an individualized level. Opening a dialogue with patients to discuss their unique needs, concerns and lifestyle can help decide which treatment is right for them.

To learn more about these medications and how to decide which is best for your patients, visit our medications pages:


Physicians can help patients save money with fast and discreet home deliveries of their ED medications, including Tadalafil and Sildenafil.

We offer Tadalafil in 5, 10 and 20 mg doses and Sildenafil in 20, 50 and 100 mg doses.

Learn more about these medications and others that we offer here.

If you have questions about implementing these treatment options or to get started prescribing these medications to ED patients, fill out our contact form.