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Erectile Dysfunction

Branded Cialis®

Erectile Dysfunction

Branded Cialis®

Cialis® is an FDA-approved ED medication that’s helped millions of men enjoy more satisfying sex. Its active ingredient, tadalafil, is clinically proven to help men with ED get and maintain erections.

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Through Rex MD, a licensed healthcare provider can prescribe Cialis® or another ED treatment online, if appropriate. No in-person doctor visit needed. Plus, you’ll get your medication quickly and discreetly with free, rush shipping.

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Meet Cialis®
  • Clinically proven to reduce ED symptoms
  • Flexible dosage options
  • Taken daily or as-needed for spontaneous sex

How to take it

Always take Cialis® as instructed by your healthcare provider. It can be taken as-needed or daily. Cialis® usually starts to work within 30 to 60 minutes, and its effects can last for between 24 and 36 hours, so it can support erections longer than other prescription ED treatments. Cialis® is triggered by sexual stimulation, so you need to be aroused for it to work.

Common Cialis side effects

Potential side effects can include headaches, flushing, upset stomach, abnormal vision, runny or stuffy nose, back and muscle pain, nausea, dizziness, and rash. In rare cases, it can cause changes in vision or loss of sight. If you have any side effects that bother you or do not go away, talk to your provider. Do not drink alcohol to excess (more than five drinks) while taking Cialis®.

Prescription products require an online consultation with a physician who will determine if a prescription is appropriate.

Why Cialis®?

Cialis® stays in your system for longer than other ED medications so you can be ready for sex any time the mood strikes.

It can be taken daily or as-needed to help men achieve optimal erectile function.

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Inhibits PDE5

Cialis works by inhibiting an enzyme called phosphodiesterase type 5 (PDE5).

Boosts blood flow

When PDE5 is inhibited, blood is able to move more freely to the penis.

Gets you hard

More blood flow allows for harder, longer-lasting erections with sexual stimulation.

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Why choose Rex MD?

Rex MD helps eligible patients get prescription ED medications like Cialis® quickly, discreetly, and affordably — right from home. No in-person doctor visit needed.

  • The best price per pill, guaranteed

  • Free online consultation

  • Branded and generic treatment options

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  • Ongoing support from our care team

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How to take Cialis®

Always take Cialis® as instructed by your healthcare provider. Cialis® can be taken as-needed or daily. Cialis® usually starts to work within 30 to 60 minutes, and its effects can last for between 24 and 36 hours, so it can support erections longer than other prescription ED treatments. Cialis® is triggered by sexual stimulation, so you need to be aroused for it to work.

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ⓘ Important safety information ›

How to get Cialis® online through Rex MD

Free online consultation

Answering questions about your symptoms and health history.

Personalized review

If appropriate, a licensed physician will prescribe a treatment plan that meets your needs.

Fast, discreet shipping

Your medication will ship out in discreet packaging within two days.

Ongoing support

Contact our team anytime to discuss your treatment and make adjustments, if needed.

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Frequently asked questions about Cialis®

What is Cialis®?

Cialis® is a prescription medication that is used to treat erectile dysfunction.

How does Cialis® work?

Tadalafil, the active ingredient in Cialis®, treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. This increased blood flow can cause an erection.

How long does it take for Cialis® to work?

Cialis® usually starts to work within 30 to 60 minutes.

How long do the effects of Cialis® last?

Its effects can last for between 24 and 36 hours, so it can support erections longer than other prescription ED treatments.

Is 20mg Cialis® the same as 100mg Viagra®?

Ultimately, these are two different medications that are used to treat the same condition. 20mg is the maximum dose of Cialis® and 100mg is the maximum dose of Viagra. Your healthcare provider may suggest that you use 100mg of Viagra if you're prescribed Cialis® and want to change medications.

Can I take two 5mg Cialis® pills at once?

Yes, you can take two 5mg pills at once with your doctor’s approval. This will increase your dosage to 10 mg.

Does Cialis® lower blood pressure?

Cialis® relaxes arteries throughout the body, which can cause your blood pressure to decrease. This can cause mild increases in heart rate. Patients with low blood pressure should use Cialis® with caution.

How do I avoid side effects from Cialis®?

Make sure you disclose all the medications you are taking during your free online consultation to avoid negative drug interactions. Additionally, share your complete medical history, including any medical conditions you have. Also, avoid excessive alcohol consumption when taking Cialis®. Lastly, follow the instructions of your provider when taking Cialis®.

Is Cialis® safe?

Yes. Cialis® is generally safe as long as you take the recommended dose and follow the instructions of your prescribing healthcare provider. Taking more than the recommended dose of Cialis® puts you at risk for serious side effects, so be sure to use your medication as directed.

How many years can you take Cialis®?

While some users might argue that they need to increase their dosage over time, there is no research to suggest that men can build immunity or tolerance to Cialis®. In other words, there is currently no recommended cut-off point for safely taking Cialis®.

Will Cialis® make you last longer in bed?

No, Cialis® doesn't make you last longer during sex. If you're climaxing earlier than you'd like (premature ejaculation) other treatments may help.

Explore Our ED Medications

Generic Viagra (Sildenafil)

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Sildenafil is the unbranded, more affordable, generic version of Viagra. It is taken on an as-needed basis for planned intimate encounters.

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Branded Viagra®

From $96 per use

This is the branded version of sildenafil.

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Generic Cialis (Tadalafil)

From $6 per use

Tadalafil is the unbranded, more affordable, generic version of Cialis. It is taken on an as-needed basis for planned intimate encounters.

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Daily Generic Cialis (Tadalafil)

From $2 per use

This is the unbranded, more affordable generic version of Cialis Daily. It is taken every day to allow for spontaneous intimate encounters.

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Rex MD is excited to announce the New
TestoRx Prescription Testosterone Therapy

TestoRx will be available in October 2024

Prescription Testosterone

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In the meantime, check out all of the Men's Telehealth Treatments and Save 95% Off with generic Viagra & generic Cialis today.

Important Safety Information

Erectile Dysfunction
Last Updated: Aug 15, 2024
Table of Contents
  1. Viagra
  2. Cialis
 

What Should You Know Before Taking Viagra?

Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.

Contraindications

Do not take Viagra® or generic Viagra® if you:

  • take medicines called "nitrates" (such as nitroglycerin)

  • use street drugs called "poppers" such as amyl nitrate or amyl nitrite, and butyl nitrate

  • take any medicines called guanylate cyclase stimulators such as riociguat (Adempas)

  • are allergic to sildenafil, as contained in Viagra® and Revatio, or any of the ingredients in Viagra®. See the end of this leaflet for a complete list of ingredients in Viagra®.

What should I tell my healthcare provider before taking Viagra® or generic Viagra®?

To make sure Viagra® is safe for you, tell your healthcare provider if you have any of the following before you take Viagra® or generic Viagra®:

  • Have or have had heart problems such as a heart attack,irregular heartbeat, angina, chest pain, narrowing of the aortic valve, or heart failure

  • Have had heart surgery within the last 6 months

  • Have pulmonary hypertension

  • Have had a stroke

  • Have low blood pressure, or high blood pressure that is not controlled

  • Have a deformed penis shape

  • Have had an erection that lasted for more than 4 hours

  • Have problems with your blood cells such as sickle cell anemia, multiple myeloma, or leukemia

  • Have retinitis pigmentosa, a rare genetic (runs in families) eye disease

  • Have ever had severe vision loss, including an eye problem called NAION

  • Have bleeding problems

  • Have or have had stomach or intestinal ulcers

  • Have liver problems

  • Have kidney problems or are having kidney dialysis

  • Have any other medical conditions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Viagra® and generic Viagra® may affect the way other medicines work, and other medicines may affect the way Viagra® and generic Viagra® works, causing side effects.

Drug Interactions

Tell your healthcare provider if you take any of the following because these drugs interact with Viagra® and generic Viagra®:

  • Medicines called "nitrates"

  • Medicines called guanylate cyclase stimulators such as Adempas® (riociguat)

  • Medicines called alpha-blockers such as Hytrin® (terazosin HCl), Flomax® (tamsulosin HCl), Cardura® (doxazosin mesylate), Minipress® (prazosin HCl), Uroxatral® (alfuzosin HCl), Jalyn® (dutasteride and tamsulosin HCl), or Rapaflo® (silodosin). Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. In some patients, the use of VIAGRA® or generic VIAGRA® with alpha-blockers can lead to a drop in blood pressure or to fainting

  • Medicines called HIV protease inhibitors, such as ritonavir (Norvir®), indinavir sulfate (Crixivan®), saquinavir (Fortovase® or Invirase®), or atazanavir sulfate (Reyataz®)

  • Oral antifungal medicines, such as ketoconazole (Nizoral®) and itraconazole (Sporanox®)

  • Antibiotics, such as clarithromycin (Biaxin®), telithromycin (Ketek®), or erythromycin

  • Other medicines that treat high blood pressure

  • Other medicines or treatments for ED

  • Viagra® and generic Viagra® contain sildenafil, which is the same medicine found in another drug called Revatio®. Revatio® is used to treat a rare disease called pulmonary arterial hypertension (PAH). Viagra® and generic Viagra® should not be used with Revatio® or with other PAH treatments containing sildenafil or any other PDE5 inhibitors (such as Adcirca [tadalafil])

Ask your healthcare provider or pharmacist for a list of these medicines, if you are not sure.

Know the medicines you take. Keep a list of them to show to your healthcare provider and pharmacist when you get a new medicine.

Viagra Side Effects

What are the possible side effects of Viagra® and generic Viagra®?

Viagra® and generic Viagra® can cause serious side effects. Rarely reported side effects include:

  • an erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, get medical help right away. If it is not treated right away, priapism can permanently damage your penis.

  • sudden vision loss in one or both eyes. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION). It is uncertain whether PDE5 inhibitors directly cause the vision loss. Stop taking Viagra® and call your healthcare provider right away if you have sudden vision loss in one or both eyes.

  • sudden hearing decrease or hearing loss. Some people may also have ringing in their ears (tinnitus) or dizziness. If you have these symptoms, stop taking Viagra® or generic Viagra® and contact a doctor right away.

The most common side effects of Viagra® and generic Viagra® are:

  • headache

  • flushing

  • upset stomach

  • abnormal vision, such as changes in color vision (such as having a blue color tinge) and blurred vision

  • stuffy or runny nose

  • back pain

  • muscle pain

  • nausea

  • dizziness

  • Rash

In addition, heart attack, stroke, irregular heartbeats and death have happened rarely in men taking Viagra®. Most, but not all, of these men had heart problems before taking Viagra®. It is not known if Viagra® caused these problems.

Tell your healthcare provider if you have any side effect that bothers you or does not go away.

These are not all the possible side effects of Viagra® and generic Viagra®. For more information, ask your healthcare provider or pharmacist.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

 

What Should You Know Before Taking Cialis

Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.

Contraindications

Who should not take Cialis® or generic Cialis®? Do not take Cialis® or generic Cialis® if you:

  • take medicines called nitrates (such as nitroglycerin)

  • use street drugs called "poppers" such as amyl nitrate or amyl nitrite, and butyl nitrate

  • take any medicines called guanylate cyclase stimulators such as riociguat (Adempas)

  • are allergic to Cialis® or any of the ingredients in Cialis®. See the end of this section for a complete list of ingredients in Cialis®.

What should I tell my healthcare provider before taking Cialis® or generic Cialis®?

To make sure Cialis® is safe for you, tell your healthcare provider if you have any of the following before you take Cialis® or generic Cialis®?:

  • Have or have had heart problems such as a heart attack,irregular heartbeat, angina, chest pain, narrowing of the aortic valve, or heart failure

  • Have had heart surgery within the last 6 months

  • Have pulmonary hypertension

  • Have had a stroke

  • Have low blood pressure, or high blood pressure that is not controlled

  • Have a deformed penis shape

  • Have had an erection that lasted for more than 4 hours

  • Have problems with your blood cells such as sickle cell anemia, multiple myeloma, or leukemia

  • Have retinitis pigmentosa, a rare genetic (runs in families) eye disease

  • Have ever had severe vision loss, including an eye problem called NAION

  • Have bleeding problems

  • Have or have had stomach or intestinal ulcers

  • Have liver problems

  • Have kidney problems or are having kidney dialysis

  • Have any other medical conditions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Cialis® and generic Cialis® may affect the way other medicines work, and other medicines may affect the way Cialis® and generic Cialis® works, causing side effects.

Drug Interactions

Tell your healthcare provider if you take any of the following because these drugs interact with Cialis® and generic Cialis®:

  • Medicines called nitrates

  • Medicines called guanylate cyclase stimulators such as Adempas® (riociguat)

  • Medicines called alpha-blockers such as Hytrin® (terazosin HCl), Flomax® (tamsulosin HCl), Cardura® (doxazosin mesylate), Minipress® (prazosin HCl), Uroxatral® (alfuzosin HCl), Jalyn® (dutasteride and tamsulosin HCl), or Rapaflo® (silodosin). Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. In some patients, the use of Cialis® or generic Cialis® with alpha-blockers can lead to a drop in blood pressure or to fainting

  • Medicines called HIV protease inhibitors, such as ritonavir (Norvir®), indinavir sulfate (Crixivan®), saquinavir (Fortovase® or Invirase®), or atazanavir sulfate (Reyataz®)

  • Oral antifungal medicines, such as ketoconazole (Nizoral®) and itraconazole (Sporanox®)

  • Antibiotics, such as clarithromycin (Biaxin®), telithromycin (Ketek®), or erythromycin

  • Other medicines that treat high blood pressure

  • Other medicines or treatments for ED

  • Adcirca® (tadalafil) is used to treat a rare disease called pulmonary arterial hypertension (PAH) and has the same active ingredient as Cialis®. Cialis® and generic Cialis® should not be used with Adcirca® or with other PAH treatments containing sildenafil or any other PDE5 inhibitors (such as Revatio® [sildenafil citrate])

Ask your healthcare provider or pharmacist for a list of these medicines, if you are not sure.

Know the medicines you take. Keep a list of them to show to your healthcare provider and pharmacist when you get a new medicine.

Cialis Side Effects

What are the possible side effects of Cialis® and generic Cialis®?

Cialis® and generic Cialis® can cause serious side effects. Rarely reported side effects include:

  • an erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, get medical help right away. If it is not treated right away, priapism can permanently damage your penis.

  • sudden vision loss in one or both eyes. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION). It is uncertain whether PDE5 inhibitors directly cause the vision loss. Stop taking Cialis® and call your healthcare provider right away if you have sudden vision loss in one or both eyes.

  • sudden hearing decrease or hearing loss. Some people may also have ringing in their ears (tinnitus) or dizziness. If you have these symptoms, stop taking Cialis® or generic Cialis® and contact a doctor right away.

The most common side effects of Cialis® and generic Cialis® are:

  • headache

  • flushing

  • upset stomach

  • abnormal vision, such as changes in color vision (such as having a blue color tinge) and blurred vision

  • stuffy or runny nose

  • back pain

  • muscle pain

  • nausea

  • dizziness

  • Rash

In addition, heart attack, stroke, irregular heartbeats and death have happened rarely in men taking Cialis®. Most, but not all, of these men had heart problems before taking Cialis®. It is not known if Cialis® caused these problems.

Tell your healthcare provider if you have any side effect that bothers you or does not go away.

These are not all the possible side effects of Cialis® and generic Cialis®. For more information, ask your healthcare provider or pharmacist.

Talk to your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What Happens if I Overdose?

Taking more than the recommended amount of Cialis® or generic Cialis® greatly increases your risk of side effects, including severe ones that can be dangerous, such as severe low blood pressure or an erection that won’t go away even after 4 or more hours (priapism). Never take more than the amount prescribed to you by your doctor. If you have any severe side effects after taking more than the recommended amount, or even after taking the amount of medicine prescribed to you, seek out emergency medical attention immediately.