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Cialis is the brand name for tadalafil, a medication used to treat erectile dysfunction (ED).

Tadalafil is in a class of drugs called phosphodiesterase-5 (PDE5) inhibitors. Cialis is taken as an oral tablet either as a low-dose daily medication or as a higher-dose “on-demand” medication.

Generic Cialis, tadalafil, has been on the market since 2018. The active ingredient, tadalafil, is the same in the brand and generic forms of the drug. The only real difference between them is cost.

A partnership between ICOS Corporation and Eli Lilly and Company (Lilly ICOS LLC) developed Cialis, which received approval from the Food and Drug Administration (FDA) in 2003.

Eli Lilly eventually bought ICOS and held an exclusive patent on the drug until it reached a settlement in 2018 with companies looking to offer a generic version of the popular ED medication.

Among the companies that produce generic Cialis with FDA approval are:

  • Accord Healthcare
  • Ajanta Pharma
  • Alembic Pharmaceuticals
  • Amneal Pharmaceuticals
  • Apotex Corp
  • AvKARE, Inc
  • AvPAK
  • Burel Pharmaceuticals
  • Camber Pharmaceuticals
  • Cipla
  • Dr. Reddy’s Laboratories
  • Lupin
  • Macleods Pharmaceuticals
  • Mylan
  • Nivagen Pharmaceuticals
  • Northstar Rx LLC
  • Prasco Laboratories
  • Sunshine Lake Pharma Co.
  • Teva Pharmaceutical Industries
  • Torrent Pharmaceuticals Limited
  • Unichem Pharmaceuticals
  • Zydus Pharmaceuticals

ED

Cialis is used primarily to treat ED.

A study published in Therapeutics and Clinical Risk Management notes that Cialis is a generally safe and effective option for people in the general ED population as well as those with difficult-to-treat erectile dysfunction.

Benign prostaic hyperplasia

Cialis and generic tadalafil are also prescribed to treat the symptoms of benign prostatic hyperplasia (BPH), also known as an enlarged prostate.

Pulmonary arterial hypertension

Tadalafil is also FDA approved to treat pulmonary arterial hypertension (PAH), which is high blood pressure affecting the arteries in the lungs. The dose for PAH is 20 mg.

Adcirca makes the version of tadalafil used to treat PAH.

Cialis and generic tadalafil are available with a prescription only. There is no over-the-counter version, though there have been efforts in recent years to develop a nonprescription version of tadalafil.

Phosphodiesterase type 5 (PDE5) inhibitors work by binding to an enzyme called PDE5, which normally breaks down cyclic guanosine monophosphate (GMP) molecules.

Cyclic GMP helps relax the smooth muscles within the blood vessels of your penis. This process significantly increases blood flow to these blood vessels, leading to an erection.

Cialis and other PDE5 inhibitors don’t cure ED or increase libido. Physical and psychological arousal are still necessary for the medications to help achieve and sustain an erection.

When sexually aroused, the parasympathetic nervous system activates, triggering the release of a molecule called nitric oxide (NO). The increased presence of NO is what increases the production of cyclic GMP.

Cialis is available as an oral tablet in several dosages, allowing individuals to take a low-dose tablet daily or a stronger dose on demand prior to sexual activity.

The daily doses are available in 2.5 mg and 5 mg tablets. Doctors usually start their patients on the 2.5-mg dose, though 5 mg may be appropriate if needed for greater efficacy.

For some people, a daily dose of 5 mg may be too much and lead to undesirable side effects.

On-demand doses are available in 10-mg and 20-mg doses. Your doctor usually recommends starting with a 10-mg dose and move up to 20 mg if a stronger dose is needed to achieve the desired results.

A study published in the Journal of Sexual Medicine found that while low-dose daily use may have produced a slightly weaker effect than the higher-dose on-demand use in some study participants, there did not appear to be a major benefit with one approach over the other.

To get the most out of Cialis:

  • With an on-demand dose, take it at least 30 minutes prior to sexual activity, though understand that it could take up to 2 hours to take effect.
  • Take daily doses at about the same time every day.
  • Focus on managing stress.
  • Maintain healthy communication with your partner.

Some of the most common side effects associated with Cialis are:

  • headache
  • flushing
  • indigestion
  • congestion
  • back pain and muscle aches

Cialis is more likely to cause myalgia (muscle pain) when compared with other PDE5 inhibitors, according to a 2017 study on ED treatment published in the journal Nature Reviews Disease Primers.

Many users of Cialis or generic tadalafil do not experience side effects, and those who do often have minor complaints that tend to go away once the drug is out of their system.

Muscle aches may last up to 2 days or so after taking your last dose.

More serious potential symptoms include priapism, an abnormal, sometimes painful erection that lasts more than 4 hours.

Other concerning symptoms that should prompt a visit include sudden changes in vision and hearing — occasionally with tinnitus and dizziness.

Unlike some other PED5 inhibitors, Cialis may be taken with or without food. It’s unlikely to have any impact on its effectiveness or side effects.

Avoid taking with high fat foods and meals

You should avoid high fat meals when using Cialis, as too much fat may affect how well the medication works and how quickly it takes effect.

Avoid grapefruit juice

Grapefruit and grapefruit juice can enhance levels of Cialis in the bloodstream, potentially increasing negative side effects.

Avoid heavy alcohol drinking

Moderate alcohol consumption should have little effect on how Cialis works, though heavy alcohol consumption can make it difficult to achieve an erection even with the use of an ED medication.

Know your other medications

Cialis may interact with certain medications. In particular, you should not take Cialis if you are also taking nitrates, which are medications that widen arteries to allow greater blood flow.

Nitrates are typically prescribed to treat angina (chest pain brought on by narrowed coronary arteries) or heart failure.

When taken with nitrates or antihypertensive medications called alpha- blockers, Cialis could cause a dangerous drop in blood pressure.

Cialis may lead to similar problems when used in combination with other antihypertensive drugs.

Other classes of drugs that may interfere with Cialis include:

  • antiseizure medications
  • certain antibiotics
  • HIV medications
  • oral antifungal medications

You should also avoid taking two PDE5 inhibitors in one day, as this can lead to a dangerous drop in blood pressure and other serious side effects.

Cialis and generic tadalafil are equally effective. The FDA works to ensure that the generic versions of all brand-name medications provide the same clinical benefits.

The main difference between Cialis and generic tadalafil is the cost.

Though prices vary considerably dependent on the manufacturer and pharmacy where you are buying the medication from, Cialis typically costs around $365 for 30 tablets. The generic versions costs around $100 for 30 tablets.

While Cialis is widely prescribed around the world, the most well-known PDE5 inhibitor is still Viagra (sildenafil), which is the first medication in this class of drugs to hit the market.

In addition to Cialis and Viagra, the other PDE5 inhibitors include:

  • vardenafil (Levitra, Staxyn)
  • avanafil (Stendra)

All of these medications work best when used in combination with doing other things to support your overall health, especially those things that directly impact your cardiovascular health.

In addition to PDE5 inhibitors, there are alternatives to medications some people consider along with healthy habits. Among them are supplements and pill-free options, such as:

  • L-arginine, an amino acid that helps manufacture nitric oxide
  • Red ginseng, also known as Panax ginseng, an herb sometimes taken to lower inflammation
  • Rhodiola rosea, an herbal supplement associated with increased energy
  • Acupuncture, though research has shown conflicting results

Other habits that help sexual function

Adopting a healthier lifestyle is important. This includes things like getting regular exercise as much as you’re able to, quitting smoking, if you smoke, getting 7 to 8 hours of sleep each night, consuming nutrient-dense foods as often as possible, and managing stress.

Healthline

Cialis and Viagra each have their own pros and cons, though the medications work similarly in the body.

Cialis has the advantage of lasting longer, with effects often lingering as long as 36 hours after taking the tablet.

Viagra usually lasts about four hours. Viagra is also an on-demand medication only, so the spontaneity that daily Cialis use allows is not an option with Viagra.

Cialis, however, is associated with muscle aches in the limbs in some users, a side effect not associated with Viagra. Some research suggests that Viagra use may be associated with vision problems.

You can also find generic versions of both Cialis and Viagra.

Your lifestyle and personal experience with a particular medication may help you determine if Cialis, Viagra, or another PDE5 inhibitor is the right choice.

Cialis isn’t available over the counter. Your doctor has to prescribe Cialis for ED or other conditions the medication treats.

You may also be able obtain this medication with the help of telemedicine services.

Companies such as Hims, Inc. and Roman offer online consultations with physicians who can prescribe ED medications that are then mailed to your home.

The cost of these online services can sometimes exceed conventional healthcare, though the convenience and discretion of this type of telemedicine service is appealing to many individuals.

Online ED treatment services

Healthline

Cialis, the brand version of the PDE5 inhibitor tadalafil, is one of the most widely prescribed ED medications in the world.

Generic tadalafil has been available since 2018 and has proven to be just as effective and safe as the brand name.

The drug is available in daily low doses that keep the medication in your system and allow for greater spontaneity. It’s also available in stronger, on-demand doses.

While Cialis and other ED drugs don’t “cure” the condition, they can treat the primary symptom by helping achieve and maintain erections.

If ED is affecting your life and relationship, you may want to consider trying tadalafil in some form.

It’s available by prescription only, so consult with a doctor about this and other possible ED treatments.