Tadalafil vs. Sildenafil

Both are prescription PDE5 inhibitors used to treat erectile dysfunction and work through the same general pathway. The main practical differences are duration and timing: tadalafil has a longer duration of pharmacologic effect, while sildenafil has a shorter one and is generally used in relation to anticipated sexual activity.

Tadalafil is the active ingredient in Cialis®, which is a registered brand name of its manufacturer. Tadalafil is also available in generic prescription products containing the same active ingredient.

Sildenafil is the active ingredient in Viagra®, a registered brand name of its manufacturer. Sildenafil is also available in generic prescription products containing the same active ingredient.

Both begin working within the timeframes described in their approved prescribing information, and the difference is often smaller than people expect. Onset varies between individuals and can be affected by dose, food, alcohol, other medications and physiology. A high-fat meal can slow sildenafil's absorption; tadalafil's absorption is not considered to be meaningfully affected by food.

Tadalafil generally has a longer duration of pharmacologic effect. That describes a window during which the medication may help support an erectile response when sexual stimulation occurs — not a continuous erection.

Neither is universally better. They are different approaches, and which may be appropriate depends on your medical history, current medications, previous treatment, tolerability and preferences.

No. Neither medication is categorically stronger. They differ in duration and timing characteristics rather than in being more or less powerful, and doses are not directly comparable between them.

Neither has categorically fewer. Commonly reported effects overlap and include headache, flushing, indigestion, nasal congestion and dizziness. Back pain and muscle aches are described with tadalafil; visual disturbances are described with sildenafil. Individual tolerability varies.

Tadalafil has approved dosing approaches that can include once-daily use for certain patients and indications. That does not mean daily use is right for everyone. Only your physician can determine which approach, if any, is appropriate for you.

A high-fat meal can slow the absorption of sildenafil, which may delay when its effect begins. Follow the instructions your physician gives you and the approved prescribing information for your product.

Absorption of tadalafil is not considered to be meaningfully affected by food according to approved prescribing information. Alcohol, however, can contribute to blood-pressure effects and dizziness with either medication.

Yes. Both medications support the body's own erectile response. Sexual stimulation is generally still required — neither one produces an erection on its own.

No. Neither medication directly increases testosterone. If low testosterone is a concern, that is a separate medical evaluation your physician can discuss with you.

No. PDE5 inhibitors are not aphrodisiacs and do not increase libido. They act on blood flow in response to sexual stimulation. Low desire has different causes and warrants its own conversation with a physician.

Switching is a medical decision. A physician can review your response, side effects, other medications and preferences and discuss whether a different approach may be appropriate and how any change should be handled.

The same applies in the other direction. Tell your physician what you have tried, how you used it and what happened — that information is what makes the next decision a good one.

Never on your own. Combining PDE5 inhibitors can affect the safety profile of treatment. In selected circumstances a physician may consider a customized combination approach when clinically appropriate; compounded formulations are not FDA-approved and are not appropriate for everyone.

Both are established prescription medications with important warnings, precautions, contraindications and drug interactions. Safety depends on your individual health, which is why a physician evaluation is required before treatment.

They are not appropriate for patients taking nitrates, and may be inappropriate with certain cardiovascular conditions, low or unstable blood pressure, some eye conditions, significant liver or kidney impairment, or certain interacting medications. Your physician reviews this with you.

No. PDE5 inhibitors can cause a dangerous drop in blood pressure when used with nitrate medications, including nitroglycerin, isosorbide and recreational nitrates known as poppers. Tell your physician if you take nitrates in any form, even occasionally.

Yes. Tadalafil and sildenafil are prescription medications in the United States and require evaluation by a licensed physician.

The physician visit is $29. It covers your private online visit with a licensed NORBU MD physician, including discussion of your symptoms, health and treatment options.

No. The $29 fee covers the physician visit only. Medication, laboratory testing and other services, if applicable, are separate.

Yes. You can raise tadalafil, sildenafil, customized treatment and any other questions during your visit, and your physician can explain which options may be appropriate given your health.