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Erectile dysfunction meds, like Viagra and Cialis, can help maintain an erection. However, the side effects, dosage schedule, and other factors are different for each. Read on to see how they stack up.
Viagra and Cialis are oral medications used to treat erectile dysfunction (ED). You may also know them by their generic names:
- sildenafil (Viagra)
- tadalafil (Cialis)
About 30 million men in the United States occasionally have a problem with getting or keeping an erection, according to the Urology Care Foundation. When ED becomes a problem, many turn to these oral ED medications to help address the issue.
The medications work in similar ways. However, they also have some key differences, such as when you take them, how long they work, and what their side effects are.
How ED meds work: A refresher
Viagra and Cialis are in a class of medications called phosphodiesterase type 5 (PDE5) inhibitors. These drugs work by blocking the PDE5 enzyme.
These medications boost a chemical in your body called nitric oxide, which encourages the muscles in your penis to relax. This allows blood to flow freely so you can get and maintain an erection when you’re aroused.
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Unlike Viagra and the other PDE5 inhibitors, Cialis is also approved to treat enlarged prostate.
Both Viagra and Cialis can be taken 30 minutes before sexual activity. However, Cialis lasts much longer and is noteworthy for the amount of time it remains in your body. You may feel the effects of the drug up to 36 hours after you take it.
The fact that it comes in a low dose of 2.5 milligrams (mg) also means that you can take Cialis every day. A daily dose will ensure that the drug’s always in your system.
If you take Cialis, there’s a chance of limb pain. This side effect is not associated with any other oral ED drugs.
| Similarities | Differences |
|---|---|
| They’re both PDE5 inhibitors. | Cialis lasts up to 36 hours in the body, while Viagra lasts 4–6 hours in the body. |
| Both are taken 30 minutes before sex. | Cialis can cause limb pain, while Viagra can cause vision change, rash, and dizziness. |
| Side effects include flushing, back pain, headaches, muscle pain, and upset stomach. |
Pros of Cialis
- lasts longer than Viagra
- unaffected by food intake
Cons of Cialis
- may cause limb pain
- side effects can include nausea, diarrhea, and lowered blood pressure
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Pros of Viagra
- leaves the body faster than Cialis, which may be helpful if you’re concerned about side effects
Cons of Viagra
- may cause vision changes, rash, nausea, and dizziness
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Here are the basic features of each of these drugs. Prices are estimated through Optum Perks‘ pharmacy search.
Prices for each product is based on 10 tablets of the typical (or first mentioned) dose. The brand name drug is listed first, then the generic drug (if available) price is listed.
| Pricing | Generic available? | Dosage strengths | When to take | Effects last | How to store | |
|---|---|---|---|---|---|---|
| Viagra | sildenafil | $911 for Viagra; $3.55 for sildenafil | yes | 25 mg, 50 mg, 100 mg | 30-60 minutes before sex | 4 hours | around room temperature, between 68–77°F (20–25°C) |
| Cialis | tadalafil | $590 for Cialis; $16.30 for tadalafil | yes | 2.5 mg, 5 mg, 10 mg, 20 mg | 30 minutes before sex | up to 36 hours | at 77°F (25°C) |
These medications are available in various doses and can be taken with or without food. However, taking Viagra, after eating a high fat meal does slow the rate of absorption.
Do not take any of these medications more than once in a 24-hour period.
The side effects of these medications are mostly similar, and they’re usually mild. Tell your doctor if you have any side effects that linger and do not go away on their own.
Below are the most common side effects, according to their manufacturers:
| Side effect | Viagra | Cialis |
|---|---|---|
| stuffy or runny nose | x | x |
| headache | x | x |
| dizziness | x | |
| upset stomach | x | x |
| nausea | x | |
| indigestion | x | x |
| vision changes | x | |
| rash | x | |
| flushing | x | x |
| back pain | x | x |
| pain in the limbs | x | |
| muscle aches | x | x |
| sore throat |
Priapism warning
If you have an erection that lasts longer than 4 hours, contact your doctor right away. This condition, known as priapism, is a risk associated with all of these ED drugs.
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To get any ED medication, you’ll need a prescription. You can get a prescription through your primary care doctor or online through a telehealth company. Online telehealth companies will typically list their prices on their website so you can anticipate what your final cost will be.
However, prices can vary if you are buying ED medications through a local pharmacy based on the type of drug and dosage you have been prescribed. Your local pharmacy should be able to share their price with you ahead of sending in your prescription.
Unless prescribed by a doctor, online ED medications are not approved by the Food and Drug Administration. They may contain ineffective or harmful ingredients.
Does insurance cover ED pills?
If you have health insurance, keep in mind that most insurance companies will not cover the cost of your prescription. But if you have certain medical conditions, your insurance plan may pay for the drug with prior authorization.
The exact price you pay for any drug will depend on your insurance plan, if you have one, and your pharmacy.
If you’re on a tighter budget, it’s also worth considering generic versions of Viagra and Cialis. They can be just as effective at treating ED and are available at a fraction of the cost.
If your insurance company covers brand-name ED medications, they’re very likely to cover generics, too, which will bring down the price even further.
If your insurance plan doesn’t cover ED medication or you don’t have insurance, you can still get FDA-approved medication through a reputable source — but the price will be higher.
Online ED treatment companies, like Roman, Hims, RexMD, and Lemonaid, all offer ED medication (brand name and generic) even without insurance.
Because these medications require a doctor’s prescription, you’ll need to meet with a doctor first. Most of these online providers allow you to meet with a licensed doctor in your state virtually.
These prices can vary based on your state, subscription package discounts, and whether you have the prescription mailed to you or filled through a pharmacy.
Here’s a quick look at what you can generally expect to pay, as of May 2024, through these services:
| Viagra | Generic Viagra (sildenafil) | Cialis | Daily Generic Cialis (tadalafil) | Generic Cialis (tadalafil) | |
|---|---|---|---|---|---|
| Roman | $90 per dose | $4-$10 per dose | $20-$80 per dose | $8 per dose | $11-$44 per dose |
| Hims | $139 per dose | $4-$10 per dose | $958 per month | $82 per month | $82 per month |
| RexMD | $96 per dose | $2-$6 per dose | $29 per dose | $2 per dose | $6 per dose |
| Lemonaid | — | $2 per dose | — | $50 per pill | $65 per pill |
Each drug comes with the risk of drug interactions. Since PDE5 inhibitors work on the body in similar ways, Viagra and Cialis lead to similar interactions.
These drugs interact with:
- nitrates, such as isosorbide mononitrate (Monoket) and nitroglycerin (Nitrostat)
- certain blood pressure drugs, such as calcium channel blockers
- alpha-blockers, which can treat high blood pressure or an enlarged prostate
- certain pulmonary hypertension drugs, such as riociguat (Adempas)
- protease inhibitors, a class of HIV medications
- antifungal drugs, such as ketoconazole and itraconazole (Onmel, Sporanox)
- antibacterial drugs, such as clarithromycin (Biaxin)
Avoid drinking alcohol excessively while on any PDE5 inhibitor. Do not combine them with different ED drugs.
Cialis may also be less effective if used alongside antiseizure medications such as carbamazepine (Tegretol) and phenobarbital.
For specifics on which medications are safe for you to use, it’s best to consult your doctor or pharmacist.
In some cases, using these medications may mean you need to completely avoid PDE5 inhibitors. In other cases, your doctor or a healthcare professional may adjust your medication dosage, which can help lower the possibility of drug interactions while using PDE5 inhibitors.
It’s normal to lose your erection sometimes. Several factors can cause short-term erection issues, from anxiety and stress to just simply not being aroused or interested in a sexual encounter.
But if you’re having difficulties becoming erect or maintaining an erection throughout sex several times a week for longer than 4 weeks, it may be worth talking with a doctor to see whether you may be experiencing ED.
While ED can be more common as someone ages, it can affect males at almost any age. Talk with your doctor about what you have been experiencing. Ask them about what treatments they recommend.
Sometimes, just making lifestyle changes, like to your nutrition, work routine, or home life, can improve ED symptoms.
If your doctor believes you could benefit from ED medication, they can discuss your treatment options and prescribe the best ED medication for you.
Also, your doctor can check in with you if you start to experience any side effects from using Viagra or a similar ED medication.
No. Although Cialis and Viagra are both PDE5 inhibitors that boost nitric oxide in your body to help with ED, they’re different medications.
Cialis comes in a lower dose than Viagra and can be taken daily. Also, the effects of Cialis last longer than the effects of Viagra.
It depends on the individual and the level of arousal. It’s recommended that you take Cialis 30 minutes before engaging in sexual activity, but it may take as long as 2 hours to take effect. Cialis also requires sexual stimulation in order to work, so arousal also factors into this equation.
These medications are meant to help you have an erection long enough to have sex. However, medications like Viagra aren’t approved to treat premature ejacul*tion.
It’s unnecessary to take Viagra and Cialis together. They’re both PDE5 inhibitors that help achieve the same goal. Your doctor can help you decide which would be best for you, but there’s no need to take both.
It depends on the individual. While all ED medications help achieve the same goal, they differ in dosage, length of effects, and potential side effects. Consider all of these factors when determining which ED medication might work best for you.
If you have ED, consider talking with your doctor about Viagra and Cialis. Tell your doctor if you take other over-the-counter (OTC) or prescription drugs or supplements. Be sure to mention all other health conditions you have.
When used correctly, each of these drugs has been shown to help people with ED. Take them exactly as your doctor prescribes, and be sure to let them know if you have questions or concerns.
All of these medications have been shown to lead to good results, but it may take a little time and patience to find the right one for your needs. If one drug does not work or produces unpleasant side effects, you can try another one.
It may also take some trial and error to find the dosage that works best for you. If you’re not sure that using ED medication is right for you, you can also give natural ED treatments a try.
If you’re considering natural ED treatments, talk with your doctor or a healthcare professional first to learn more about risks, benefits, and potential drug interactions.
