ED Treatment

Tadalafil: Uses, Dosage, Solutions, and More

October 29, 2021

There are several options for guys looking to manage the symptoms of erectile dysfunction (ED).

The most popular and most effective are prescription ED medications. Each have their benefits, and one of the more popular choices in recent years has been tadalafil.

What Is Tadalafil? 

Tadalafil is the active ingredient found in the brand name medication Cialis®. 

The Food and Drug Administration (FDA) first approved tadalafil for use in the United States on November 21, 2003. Since then, it has become an increasingly popular choice for the treatment of ED. 

Although Viagra® and its generic counterpart sildenafil are still the leading choice for prescriptions in the U.S., Cialis has made up a lot of ground in recent years. According to data from 2018, three in every ten prescriptions for erectile dysfunction were for either generic tadalafil or brand name Cialis. 

In addition to managing erectile dysfunction, tadalafil can also be prescribed to treat benign prostatic hyperplasia (i.e enlarged prostate) and pulmonary arterial hypertension. 

How Does Tadalafil Work?

Tadalafil belongs to a drug class known as phosphodiesterase type 5 (PDE5) inhibitors. The most effective erectile dysfunction medications all belong to this class of drugs, including sildenafil (Viagra), vardenafil (Levitra®), and avanafil (Stendra®). 

Regardless of which one you take, each of these PDE5 inhibitors work to increase the blood flow to your penis. The mechanism of action breaks down like this:

  1. When you encounter physical or visual sexual stimulation, you become aroused.
  2. Your brain sends chemical messages throughout the body that trigger the beginnings of the erection process. The primary chemical messenger is nitric oxide, and which is sent through your bloodstream and into your penis. 
  3. Nitric oxide increases the production of another chemical known as cyclic GMP.
  4. It’s this chemical that relaxes the smooth muscles and blood vessels in your penis, as well as increases blood flow.
  5. PDE5 is a naturally occurring enzyme located in the walls of your blood vessels. Its function is to regulate cyclic GMP, and when released it works to break down cGMP. This restores your blood vessels and muscles to their normal, resting state.
  6. PDE5 inhibitors like tadalafil block PDE5 from stopping the erection. Taking a PDE5 inhibitor is like removing the brakes on a car.
  7. As a result, your blood vessels and muscles stay relaxed, your blood flow is increased, and you will be able to achieve and maintain an erection. 

During an erection, your penis can hold as much as 7x its normal blood capacity.

What Are the Most Common Doses of Tadalafil? 

One of the things that separates tadalafil from the other PDE5 inhibitors is dosage.  

Each of the other PDE5 inhibitors are designed to be taken when needed, or "on demand." They are recommended to be taken at least 30 minutes to an hour before engaging in sexual activities. 

Tadalafil can also be taken “as needed” in doses of 5, 10 or 20 milligrams. Unlike the other PDE5 inhibitors, however, tadalafil also offers doses that are small enough that they can be taken daily: at 2.5 and 5 milligrams. This daily dosing regimen allows for a bit more spontaneity with sexual activities, as the effects of tadalafil build and remain in your system until the next time you take a dose. It’s recommended that they be taken at the same time each day, but the effects can last for up to 36 hours after taking a pill.

Tadalafil's higher doses are also known for this 36 hour effect. The effects of Viagra and Levitra typically last for 4 hours, allowing for intimacy any time during that window. Tadalafil is known as "the weekend pill" for a reason: its effects last for 36 hours, even when taking the higher doses and not on a daily regimen.


Are There Side Effects To Taking Tadalafil? 

Just like most other pharmaceuticals, there are known side effects to Cialis, generic tadalafil, and PDE5 inhibitors in general. 

Since these drugs have a strong impact on blood flow, it’s not recommended that you mix them with other medications that also affect blood flow or blood pressure. This includes nitrates, alpha-blockers, blood thinners, beta-blockers, or any medications for high blood pressure. 

It’s important that you tell your prescribing doctor about any medication that you're taking, as drug interactions can cause dangerously low blood pressure that may require emergency medical help. 

As long as you don’t mix any of these medications, most of the potential side effects aren’t dangerous. 

Tadalafil's most common side effects include:

  • Headaches
  • Stuffy nose
  • Mild muscle pain and aches
  • Feeling lightheaded
  • Prolonged erection
  • Stomach upset

Typically these side effects only last while the drug is in your system and get better with time. Since tadalafil can last up to 36 hours, you may want to consider a trial run before getting a prescription for daily usage. 

If you experience any of the following adverse effects during sexual activity, stop what you’re doing and seek emergency medical advice as this may be a sign of a heart problem or an allergic reaction:

  • Vision changes such as vision loss or blur
  • Sudden hearing loss
  • Flushing in the body or face
  • Difficulty breathing
  • Dizziness
  • Nausea
  • Back pain or chest pain (angina)
  • Swelling of the lips, tongue, or throat
  • Hives

How Effective Is Tadalafil?

Tadalafil has roughly the same rate of success as the other PDE5 inhibitors: between 70 and 75 percent. These drugs won’t have the same effect on everyone and there are a few reasons why taking them may not work. 

For starters, they rely on the release and function of nitric oxide or stimulus to begin. If you are unable to become aroused as the result of a mental health issue or major physical impairment, then they may not work. 

PDE5 inhibitors might also fail to achieve their purpose if your testosterone levels are too low. If you think you might have low testosterone, your doctor can perform a simple blood test to find out. 

Whatever the cause may be, there is largely no difference between the efficacy of the different PDE5 inhibitors. In short, all of them will likely improve your erections or none of them will.

The Takeaway

Tadalafil is one of the most popular prescription medications used to manage the symptoms of erectile dysfunction. Tadalafil (Cialis) shares common traits with other PDE5 inhibitors such as sildenafil (Viagra) and vardenafil (Levitra), and each of them essentially have the same rate of success. 

However, tadalafil does offer its users something that the others do not: the ability to be taken in daily doses instead of as-needed before sex, and a longer timeframe to initiate sex. Instead of having to plan sexual activities ahead of time, tadalafil offers some freedom. 

That's why it's preferred by most men and their partners.

Curious if ED meds are right for you? Try tadalafil yourself, if prescribed, with our online ordering process. Easy, fast, affordable - click here to get started.



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