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Compare Tadalafil vs. Sildenafil

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Tadalafil (Cialis) and sildenafil (Viagra) are both medications used to treat erectile dysfunction (ED), but they have some key differences. Tadalafil can also treat benign prostatic hyperplasia (BPH), while sildenafil is only approved for ED. Tadalafil can be taken either as needed or daily, offering more flexibility, whereas sildenafil is only taken as needed. Tadalafil lasts up to 36 hours, providing a longer window of effectiveness compared to sildenafil, which lasts up to 4 hours. Both medications are available as lower-cost generics. Common side effects for both include headaches, flushining, and indigestion. Neither medication should not be taken with nitrates due to the risk of dangerously low blood pressure.

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  • Tadalafil (Cialis)
    Sildenafil (Viagra)
  • Tadalafil (Cialis)
    Sildenafil (Viagra)

  • Summary of Tadalafil vs. Sildenafil

    Summary for PDE-5 inhibitor
    Prescription only

    Tadalafil (Cialis) is taken by mouth either as needed before sexual activity or once daily for erectile dysfunction (ED). It's also taken once daily to treat symptoms from an enlarged prostate (benign prostatic hyperplasia, or BPH). Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include headache and indigestion. Tadalafil (Cialis) does interact with some medications, such as heart and blood pressure medications, and taking them together could lead to very low blood pressure and dizziness.

    Summary for PDE-5 inhibitor
    Prescription only

    Sildenafil (Viagra) is taken by mouth to treat erectile dysfunction (ED). You take it only as needed, typically about an hour before sexual activity (but you can take it anywhere between 30 minutes to 4 hours before sex). Don't take sildenafil (Viagra) more than once a day because doing so can put you at higher risk for serious side effects, such as vision loss or low blood pressure. It's available as a lower-cost generic.

  • Indications of Tadalafil vs. Sildenafil

    Indications for
    •Erectile dysfunction
    •Benign prostatic hyperplasia (BPH)
    Indications for
    •Erectile dysfunction (ED)

  • Pros and Cons of Tadalafil vs. Sildenafil

    Pros and Const for PDE-5 inhibitor
    Pros
    •One of the first-choice medications for treating ED
    •Can be taken either as needed or on a regular basis for those who need it more regularly
    •Lasts longer than other medications taken for ED
    •Can treat ED and BPH at the same time
    •Available as a lower-cost generic
    Cons
    •Not recommended if you've had a heart attack in the past 3 months, or a stroke or heart failure in the past 6 months
    •Can't be used if you've recently taken nitrates like isosorbide mononitrate (Monoket) or nitroglycerin (Nitrostat)
    •Takes longer to work compared to some other medications for ED
    •Can cause side effects like headache, stomach upset, and back pain
    Pros and Const for PDE-5 inhibitor
    Pros
    •One of the first-choice medications for treating ED
    •Taken only when you need it
    •Can take it 30 minutes to 4 hours before sexual activity
    •Available as a lower-cost generic
    •Comes in different strengths, so you and your provider can find which works best for you
    Cons
    •Can take some time to work, so some planning is needed
    •Can't be taken if you've had a heart attack or stroke in the past 6 months
    •Can't be used if you've recently taken nitrates like isosorbide dinitrate (Isordil) or nitroglycerin (Nitrostat)
    •Higher risk for side effects, such as headaches and flushing, for people age 65 years and older

  • Common Side Effects of Tadalafil vs. Sildenafil

    Common Side Effects for

    Once-daily use of tadalafil (Cialis) (for ED or BPH):

    •Headache (3-6%)
    •Runny nose, sore throat, and other symptoms of the common cold (3-6%)
    •Indigestion (4-5%)
    •Stomach upset (3-5%)
    •Back pain (3%)

    As-needed use of tadalafil (Cialis) (for ED):

    •Headache (11-15%)
    •Indigestion (4-10%)
    •Back pain (3-6%)
    Common Side Effects for
    •Headache (16-28%)
    •Flushing (10-19%)
    •Indigestion (3-17%)
    •Changes in vision or light sensitivity (1-11%)
    •Stuffy nose (4-9%)

  • Warnings of Tadalafil vs. Sildenafil

    Common Side Effects for
    •Heart problems
    •Low blood pressure
    •Prolonged erection
    •Vision changes
    •Hearing loss
    •Interactions with other medications
    Common Side Effects for
    •Heart problems
    •Low blood pressure
    •Prolonged or painful erection (priapism)
    •Vision changes
    •Hearing loss
    •Interactions with other medications

  • Prices with our coupons for Tadalafil vs. Sildenafil

    Learn more about Tadalafil
    Learn more about Sildenafil

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