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Compare Viagra vs. Cialis

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

Key takeaways

Sildenafil (Viagra) and tadalafil (Cialis) are both medications used to treat erectile dysfunction (ED). They belong to the same drug class, PDE-5 inhibitors, but there are some differences between them. Tadalafil is also FDA-approved to treat benign prostatic hyperplasia (BPH), while sildenafil is also approved to treat pulmonary arterial hypertension. Sildenafil is typically taken as needed, about an hour before sexual activity, and its effects last up to 8 hours. In contrast, tadalafil can be taken either as needed or daily, with effects lasting up to 36 hours, offering more flexibility for spontaneous activity. Both medications are available as lower-cost generics. Common side effects for sildenafil include headaches and flushing, while tadalafil may cause headaches and indigestion. Both medications can interact with heart and blood pressure medications, leading to dangerously low blood pressure, so it's important to discuss all medications with your healthcare provider before starting either one.

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

  • Summary of Viagra vs. Cialis

    Summary for PDE-5 inhibitor
    Prescription only

    Sildenafil (Viagra) is a tablet that's taken by mouth for erectile dysfunction (ED) in adults. It works as a phosphodiesterase-5 (PDE-5) inhibitor to help people get an erection or keep an erection that lasts for sex. You only take a dosage when you need it (usually about an hour, or anywhere from 30 minutes to 4 hours, before sex). Take sildenafil (Viagra) no more than once a day. Otherwise, it can put you at risk of serious side effects, such as vision loss or low blood pressure. Other more common side effects include headache and flushing. Sildenafil (Viagra) is a brand-name and generic medication.

    Summary for PDE-5 inhibitor
    Prescription only

    Tadalafil (Cialis) is used for erectile dysfunction (ED) and benign prostatic hyperplasia (BPH) in adults. It belongs to the drug class called phosphodiesterase 5 (PDE-5) inhibitors. Tadalafil (Cialis) is a tablet you take by mouth. For ED, you can take a dose either just before sex or once every day. And for BPH, it's taken once a day. Side effects include headache and indigestion. Tadalafil (Cialis) can interact with many medications, including blood pressure medications. Some drug interactions can lead to very low blood pressure and dizziness. Tadalafil (Cialis) is available as a brand-name and generic version.

  • Indications of Viagra vs. Cialis

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

  • Pros and Cons of Viagra vs. Cialis

    Pros and Const for PDE-5 inhibitor
    Pros
    •A first-choice medication for ED
    •Taken only when you need it
    •Can take it 30 minutes to 4 hours before sexual activity
    •Comes in different strengths, so you and your prescriber can find which works best for you
    Cons
    •Can take up to an hour to get its full effect
    •Higher risk of side effects for people 65 years and older
    •Not recommended if you've had a heart attack or stroke in the past 6 months
    •Can't take if you've recently taken nitrates like isosorbide dinitrate (Isordil) or nitroglycerin (Nitrostat)
    Pros and Const for PDE-5 inhibitor
    Pros
    •A first-choice medication for ED
    •For ED only, can take either as needed or once daily
    •Lasts longer than other ED medications
    •Can treat ED and BPH at the same time
    Cons
    •Can take up to 2 hours to get its full effect for ED
    •Can cause side effects like headache, stomach upset, and back pain
    •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 take if you've recently taken nitrates like isosorbide mononitrate (Monoket) or nitroglycerin (Nitrostat)

  • Common Side Effects of Viagra vs. Cialis

    Common Side Effects for
    •Headache (16-28%)
    •Flushing (10-19%)
    •Indigestion (3-17%)
    •Changes in vision (e.g., color tinge, blurry vision, light sensitivity; 1-11%)
    •Stuffy nose (4-9%)
    Common Side Effects for

    When taken as needed for ED:

    •Headache (11-15%)
    •Indigestion (4-10%)
    •Back pain (3-6%)

    When taken once daily for ED:

    •Headache (3-6%)
    •Indigestion (4-5%)
    •Common cold symptoms (3-4%)
    •Back pain (3%)
    •Upper respiratory tract infection (3%)

    When taken once daily for BPH:

    •Headache (2-4%)
    •Indigestion (up to 2%)
    •Common cold symptoms (2%)
    •Back pain (1-2%)

  • Warnings of Viagra vs. Cialis

    Common Side Effects for
    •Risk of heart problems in people with heart disease
    •Low blood pressure
    •Prolonged or painful erection (priapism)
    •Vision changes
    •Hearing loss
    •Interactions with other medications
    Common Side Effects for
    •Risk of heart problems in people with heart disease
    •Low blood pressure
    •Prolonged or painful erection (priapism)
    •Vision changes
    •Hearing loss
    •Interactions with other medications

  • Prices with our coupons for Viagra vs. Cialis

    Learn more about Sildenafil
    Learn more about Tadalafil

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