Sildenafil vs. Tadalafil: Which is Better for ED?

Are you looking for a chance to regain confidence and have a fulfilling intimate life? Medication treatment for erectile dysfunction (ED) can offer hope and symptom improvement for more control over your health. There are many ED medications to compare, but two leading treatments, sildenafil (Viagra^®) and tadalafil (Cialis^®), could offer the results you have been looking for. Learn more here about how they work, what sets them apart and which medication might be better for ED in your unique situation.

What is sildenafil (Viagra^®)?

Sildenafil, a generic version of Viagra^®, belongs to a class of medications called phosphodiesterase (PDE) inhibitors. It treats erectile dysfunction, premature ejaculation (PE)¹ and pulmonary arterial hypertension (PAH).² For ED, it works by relaxing blood vessels and increasing blood flow, which can help achieve erection with sexual stimulation.³

Sildenafil is an oral medication that takes approximately 30 minutes to take effect after ingestion. The effects last around four hours on average.⁴ Commonly prescribed doses range from 20 mg to 100 mg, with 50 mg being utilized the most. Suggested use is as needed, with no more than one dose per day.⁵

What is tadalafil (Cialis^®)?

Tadalafil, a generic version of Cialis^®, is also a PDE inhibitor used to treat ED, PE⁶ and PAH. For erectile dysfunction, oral medication increases blood flow to cause an erection with a sexual stimulus.⁷

The dosage depends on if tadalafil is being used as needed or daily as an ED maintenance treatment. As needed dosage is commonly 10 mg once per day as needed before sexual activity. Users can continue treatment as needed with 5 mg to 20 mg before sexual activity. On average, it takes around 30 to 45 minutes for tadalafil to take effect.⁸ However, it can take up to two hours in some cases.⁹ The effects can last up to 36 hours.¹⁰

For long-term treatment of ED, 2.5 mg per day is the common dosage, regardless of when sexual activity occurs. Maintenance on this regimen ranges from 2.5 mg to 5 mg daily.¹¹

What are the differences between sildenafil and tadalafil?

Both sildenafil and tadalafil are PDE inhibitors with similar mechanisms of action, but there are some differences. The main difference between the two medications is the time to take effect and the duration of effect.

Sildenafil is more often recommended for spontaneous use. It takes about 30 minutes to take effect and lasts around five hours. While for some users, the effects can start as soon as 30 minutes. However, recommended advice is to allow tadalafil approximately two hours before sexual activity for best results. Tadalafil effects can last up to 36 hours after ingestion making it suited for long-term use.¹²

How effective are sildenafil and tadalafil for erectile dysfunction?

PDE inhibitors, like sildenafil and tadalafil, have a promising success rate. There have been reported success rates in studies of up to 70% when using PDE inhibitors for ED.¹³

How do the side effects compare for sildenafil and tadalafil?

Sildenafil and tadalafil have several common side effects, including headache, heartburn, diarrhea, nausea, flushing and muscle pain.

Side effects unique to sildenafil include:¹⁴

• Nosebleeds

• Numbness, burning, or tingling in the arms, hands, feet or legs

• Changes in color vision sensitivity to light

• Nasal congestion

Side effects unique to tadalafil include:¹⁵

• Cough

What are common drug interactions for sildenafil and tadalafil?

There are risks associated with taking sildenafil and certain medications together. It is advised not to take sildenafil if you are on certain heart or cardiac medications, including nitrates, blood pressure medications and certain HIV medications.¹⁶

Tadalafil can have negative interactions with alpha blockers, certain antifungals, HIV protease inhibitors and medications for high blood pressure.¹⁷

Can sildenafil and tadalafil be taken together?

Taking sildenafil and tadalafil has a serious risk of dropping blood pressure to dangerously low levels.¹⁸ It is generally not recommended to take both medications together for this reason; however, there have been some studies that show using sildenafil and tadalafil together are more effective than tadalafil alone in the early stages of ED treatment.¹⁹ Always consult your medical provider before taking these two medications together to assess the risk properly.

How do costs compare for sildenafil and tadalafil?

Prices for sildenafil and tadalafil can vary. Using the generic versions, rather than name brands, can offer significant savings. The average cost of Viagra^® is around $80 per tablet of 50 mg or 100 mg strength. The average cost of Cialis^® is $12 for a 5 mg tablet and $70 per 20 mg tablet.²⁰

At RedBox Rx, sildenafil is $5 per tablet and as low as $1 per tablet with some subscriptions. Tadalafil is available for an average price of $3 per tablet but can be as low as $1 per tablet with some subscriptions.

Are sildenafil and tadalafil available over the counter?

Both sildenafil²¹ and tadalafil²² are available only by prescription in the U.S. While valid prescriptions are available online, the FDA warns against purchasing over-the-counter alternatives to sildenafil and tadalafil because of serious health concerns, including dangerously low blood pressure.²³ All ED medications prescribed by RedBox Rx are FDA-approved and considered safe under medical supervision.

Tadalafil (Cialis^®) vs. Sildenafil (Viagra^®) Comparison Chart

How RedBox Rx can help

RedBox Rx makes receiving a prescription for ED, like sildenafil or tadalafil, easy and affordable.

Benefits of RedBox Rx include:

• Transparent, affordable, flat rates for medications starting at $1 per tablet.

• Free consultations with a U.S. licensed medical professional.

• No insurance required. FSA and HSA eligible.

• No office wait times or scheduling issues typical with physical medical practices.

• Free shipping directly to you.

Start your treatment today with our ED assessment and free online consultation.