Key takeaways
- While both Viagra and Cialis effectively treat erectile dysfunction (ED), Cialis offers additional approved uses for benign prostatic hyperplasia (BPH) symptoms or a combination of ED and BPH.
- Both medications have generic versions available, sildenafil for Viagra and tadalafil for Cialis, which typically cost less and are considered equally safe and effective as their brand-name counterparts.
- It is not recommended to take Viagra and Cialis together due to their similar mechanisms of action as PDE5 inhibitors, which could increase the risk of side effects like low blood pressure.
Overview
Viagra (sildenafil) and Cialis (tadalafil) are prescription drugs used to treat erectile dysfunction. Both of these medications come as tablets you’ll take by mouth, but their dosages differ.
This article explains how Viagra and Cialis are similar and different. You can view detailed articles about Viagra and Cialis if you’d like more information about these drugs.
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Key differences between Viagra and Cialis
Viagra and Cialis are very similar medications that are both used to treat ED. They belong to the same drug class, called phosphodiesterase 5 (PDE5) inhibitors, which means they work in much the same way. However, they have some key differences:
- Active ingredient: The ingredient that makes the drug work in Viagra is sildenafil, whereas in Cialis it’s tadalafil.
- Strength: Viagra is generally given in a 50 milligram (mg) dose. Cialis is much lower, at 10 mg per dose. These dosages may change depending on the doctor’s prescription.
- Timing: Both medications are taken once per day, and both can be taken as needed before sexual activity rather than being taken daily. However, in some cases, Cialis may be prescribed at a low dose of 2.5 mg to be taken every day.
- Duration of effect: Cialis can improve erectile function for up to 36 hours after the dose. Viagra, on the other hand, remains effective for around 4 hours. Note that neither drug will give you an erection without sexual stimulation.
Cost of Viagra and Cialis
As with the cost of other medications, the cost of Viagra and Cialis can vary. Their price may be affected by:
- whether they’re covered by health insurance, if you have coverage
- the pharmacy they’re purchased from
- the quantity of tablets you’re prescribed
Whether Viagra or Cialis is cheaper will depend on these factors.
Coupons and cost savings
To view drug prices when Optum Perks coupons are applied, see this coupon page for Viagra and this coupon page for Cialis. You can also check with your doctor, pharmacist, or insurance provider.
The options described in this article may also help you save on your prescription.
Note: Optum Perks coupons cannot be used with insurance copays or benefits.
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Get free cardGeneric versions
Below is information about whether Viagra or Cialis is available in a generic version.
A generic medication is an identical copy of the active ingredient in a brand-name medication. An active ingredient is what makes a medication work. Generics usually cost less than brand-name drugs. And they’re believed to be as safe and effective as the brand-name versions.
Here’s a summary of the generic versions of Viagra and Cialis:
| Viagra | Cialis | |
|---|---|---|
| Active ingredient | sildenafil | tadalafil |
| Available as a generic | yes | yes |
If your doctor prescribed Viagra or Cialis, but you’d like to know about taking its generic version, let your doctor or pharmacist know. They can help determine whether the generic version is right for you.
Uses of Viagra and Cialis
Here’s a summary of the approved uses of Viagra and Cialis:
| Viagra | Cialis | |
|---|---|---|
| Approved uses | • erectile dysfunction (ED) | • ED • signs and symptoms of benign prostatic hyperplasia (BPH) • both ED and signs and symptoms of BPH |
| Prescribed to | adults | adults |
Cialis may sometimes be used alongside finasteride to start treatment for BPH. For this use, doctors may not prescribe Cialis with finasteride for longer than 26 weeks.
If you’d like to know more about taking either medication for your condition, ask your doctor. They can recommend whether Viagra or Cialis is an option to consider.
Dosage of Viagra and Cialis
Below is dosage information for the condition that both Viagra and Cialis are prescribed to treat. To find detailed dosage information for all conditions that Viagra and Cialis treat, see these articles about Viagra dosage and Cialis dosage.
Below are the dosages provided by the drugmakers of Viagra and Cialis. If your doctor prescribes either medication, you should follow the dosage they prescribe. They’ll advise the dosage that’s best for your condition. Do not adjust your dosage without first talking with your doctor.
Viagra’s dosage
Below is a summary of Viagra’s recommended dosage in adults. Strength is measured in milligrams (mg).
| Condition | How it’s taken | Recommended dosage | Maximum frequency |
|---|---|---|---|
| ED in adults | oral tablet | 50 mg taken as needed about 1 hour before sexual activity, but it may be taken 30 minutes to 4 hours before sexual activity. Your doctor may increase your dosage to 100 mg or decrease it to 25 mg. This is based on how well Viagra works for you or how well you tolerate it. | once per day |
Cialis’ dosage
Below is a summary of Cialis’ recommended dosages in adults. Strength is measured in milligrams (mg).
| Condition | How it’s taken | Recommended dosage | Maximum frequency |
|---|---|---|---|
| ED in adults | oral tablet | • 10 mg taken as needed before sexual activity. Your doctor may increase your dosage to 20 mg or decrease it to 5 mg based on how well Cialis works for you or how well you tolerate it. • 2.5 mg taken once per day, every day without regard to timing of sexual activity. Your doctor may increase your dosage to 5 mg once per day based on how well Cialis works for you or how well you tolerate it | once per day |
Side effects of Viagra and Cialis
Viagra and Cialis may cause mild or serious side effects. Some of the more common mild side effects of each drug are listed below. Serious side effects of Viagra and Cialis are also listed.
Keep in mind that your side effects may differ from those listed below. They can vary based on your overall health, any other medications you take, and your age.
This article doesn’t include all possible side effects of these medications. To find more information, you can view the prescribing information for Viagra and Cialis. You can also check out these articles about Viagra side effects and Cialis side effects.
Mild side effects
Below are some of the mild side effects reported with Viagra and Cialis:
| Viagra | Cialis | |
| headache | ✓ | ✓ |
| indigestion | ✓ | ✓ |
| flushing (temporary warmth, redness, or deepening of skin color) | ✓ | ✓ |
| back pain | ✓ | ✓ |
| muscle aches | ✓ | ✓ |
| mild allergic reaction | ✓ | ✓ |
Serious side effects
Below are serious side effects reported with Viagra and Cialis:
| Viagra | Cialis | |
|---|---|---|
| sudden loss of vision due to possible optic nerve damage | ✓ | ✓ |
| priapism (long lasting erection) | ✓ | ✓ |
| sudden decrease or loss of hearing | ✓ | ✓ |
| low blood pressure | ✓ | ✓ |
| heart-related side effects, including heart attack | ✓ | ✓ |
| serious allergic reaction | ✓ | ✓ |
With a lot of drugs, serious side effects are possible, but they’re not common. If you have serious side effects from Viagra or Cialis, call your doctor right away. If your symptoms are severe or you’re having a medical emergency, call 911 or a local emergency number.
Questions about Viagra and Cialis
Below, you’ll find answers to some common questions about Viagra and Cialis.
How does Viagra or Cialis compare with Levitra?
Like Viagra and Cialis, Levitra is an oral tablet approved to treat ED in adults. But brand-name Levitra is no longer available. The generic version of Levitra, vardenafil oral tablet, is available. Viagra, Cialis, and vardenafil have some similarities and differences:
- Viagra and vardenafil are only approved to treat ED. Cialis is also approved to treat the symptoms of BPH.
- Viagra, Cialis, and vardenafil all belong to a group of drugs known as phosphodiesterase 5 (PDE5) inhibitors. They all work in a similar way to treat ED, and they have similar side effects and warnings.
- The dosages of Viagra, Cialis, and vardenafil are different. Viagra and vardenafil are taken about 1 hour before sexual activity. But Viagra may be taken 30 minutes to 4 hours before sexual activity. Vardenafil doesn’t have this dosing flexibility. When Cialis is taken as needed, it may be taken any time before sexual activity.
- The costs of Viagra, Cialis, and vardenafil may differ, especially since vardenafil is a generic drug. Generic drugs usually cost less than brand-name drugs.
Talk with your doctor or pharmacist if you have questions about how Viagra, Cialis, and vardenafil compare.
Is it safe to take Viagra and Cialis together?
No, it’s not recommended to take Viagra and Cialis together. Viagra and Cialis both belong to a group of drugs known as PDE5 inhibitors. They work in a similar way to treat ED, and they have similar side effects and warnings.
Taking both of these drugs together may increase your risk of side effects, including low blood pressure.
If you have questions about how to take Viagra or Cialis, talk with your doctor or pharmacist. They can recommend the best way to take either drug. Or they can discuss other treatment options if one drug isn’t working well for your condition.
Between Viagra and Cialis, is one a better treatment for ED?
Doctors may prescribe either Viagra or Cialis to treat ED. In studies, Viagra and Cialis were both effective for this purpose.
That said, these medications differ in some ways. For instance, they have different dosages, strengths, approved uses, and costs. The effects of Cialis may last for longer than Viagra.
Keep in mind that your results from taking Viagra or Cialis may differ from those seen in studies.
Your doctor can help determine whether one option is better for your condition. They’ll recommend this based on your specific needs and health factors. Talk with your doctor if you’d like to learn more about which drug is right for you.
Warnings for Viagra and Cialis
Some medications may not be recommended for you if you have certain factors affecting your health. These are referred to as a drug’s warnings.
Some people should not take Viagra or Cialis, and others should take either medication with caution.
Before taking either medication, talk with your doctor about your health conditions, past surgeries, and any medications you take. Your doctor can recommend whether either drug is safe for you.
Warnings for Viagra and Cialis are summarized in the table below:
| Viagra | Cialis | |
|---|---|---|
| taking certain other medications, including nitrate drugs or alpha-blockers | ✓ | ✓ |
| certain heart problems, such as heart disease | ✓ | ✓ |
| pulmonary hypertension | ✓ | ✓ |
| high or low blood pressure | ✓ | ✓ |
| priapism | ✓ | ✓ |
| irregular penis shape, such as Peyronie’s disease | ✓ | ✓ |
| blood cell problems | ✓ | ✓ |
| bleeding problems | ✓ | ✓ |
| stomach ulcers | ✓ | ✓ |
| severe vision loss or optic nerve damage | ✓ | ✓ |
| retinitis pigmentosa | ✓ | ✓ |
| sudden decrease or loss of hearing | ✓ | ✓ |
| consuming large amounts of alcohol | ✓ | |
| kidney or liver problems | ✓ | ✓ |
| allergic reaction to either drug or any of their ingredients | ✓ | ✓ |
You can view more detailed articles about Viagra and Cialis if you’d like to know more about the warnings for these drugs. You can also view the prescribing information for Viagra and Cialis.
Disclaimer: While Optum Perks strives for factual, comprehensive, and current information, this article is not a substitute for a licensed healthcare professional’s expertise. Always consult a doctor before taking or discontinuing any medication. Drug information is subject to change and may not cover all uses, directions, precautions, warnings, interactions, reactions, or adverse effects. The lack of a warning does not guarantee a drug’s safety, effectiveness, or appropriateness for all patients or specific uses.