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Comparison: Is ‍20mg Cialis Equal to 100mg Viagra?

Comparison: Is ‍20mg Cialis Equal to 100mg Viagra?

By Kire Stojkovski M.D
Editor Jonathan Hoarau Published 16 July 2023
Time to read 4 min

Erectile dysfunction (ED) is a common issue that affects millions of men worldwide. The development of phosphodiesterase type 5 (PDE5) inhibitors, such as Cialis and Viagra, has revolutionized the treatment of this condition. 

Although both medications are effective in treating ED, there are critical differences between them that may influence your choice. This article will explore the question: Is 20mg Cialis equal to 100mg Viagra? We will compare their active ingredients, effectiveness, side effects, and other factors to help you make an informed decision.

Overview of Cialis and Viagra

Cialis and Viagra are both PDE5 inhibitors used to treat ED. They work by relaxing the smooth muscle in the blood vessels of the penis, allowing increased blood flow and facilitating an erection. While both medications share similarities in their mechanism of action, they differ in terms of active ingredients, duration of effect, and potential side effects.

Active Ingredients

Cialis contains the active ingredient tadalafil, while Viagra contains sildenafil. Both substances belong to the PDE5 inhibitor class of medications, which help enhance the effects of nitric oxide, a chemical released during sexual arousal that relaxes the smooth muscle in the penis and increases blood flow.

Effectiveness and Duration

Both Cialis and Viagra are effective in treating ED. However, their duration of action differs significantly. Cialis can last up to 36 hours, earning it the nickname “The Weekend Pill.” In contrast, Viagra’s effects typically last between 4 to 6 hours.

Side Effects

The side effects of Cialis and Viagra can be similar, as both drugs are PDE5 inhibitors and work in similar ways. However, some side effects may be more common or severe with one drug over the other.

Comparison of Cialis 20mg and Viagra 100mg

To determine if 20mg Cialis is equal to 100mg Viagra, let’s delve deeper into the specifics of each medication.

Onset of Action

Cialis generally works within 15-20 minutes, whereas Viagra takes about 30 minutes to 1 hour to become effective. The rapid onset of action with Cialis may benefit some users, allowing for more spontaneity in sexual activity.

Duration of Effect

As mentioned earlier, Cialis lasts significantly longer than Viagra. The 36-hour duration of Cialis allows for more flexibility in sexual activity, as users do not need to plan their dosage around intercourse. In contrast, Viagra’s 4-6 hour window may be more suitable for those who prefer a shorter duration of action.

Food Interactions

Cialis is not affected by food, meaning it can be taken before or after a meal without influencing its efficacy. On the other hand, Viagra may be less effective when taken with a high-fat meal, as it can slow down the drug’s absorption.

Dosage and Administration

Cialis is available in 2.5mg, 5mg, 10mg, and 20mg tablets, with the latter being the maximum recommended dose for treating ED. It can be taken as needed or as a once-daily medication at a lower dose.

Viagra is available in 25mg, 50mg, and 100mg tablets. The recommended starting dose is 50mg, with the option to increase to 100mg if the desired effects are not achieved.

Side Effects Profile

While Cialis and Viagra share some common side effects, such as headaches, flushing, and indigestion, there are also some differences. Cialis users may experience limb pain, which is not reported with Viagra. Conversely, Viagra may cause vision changes, rash, and dizziness, whereas these side effects are less common with Cialis.

Drug Interactions

Both Cialis and Viagra can interact with other medications, particularly those prescribed for heart disease or hypertension. It is crucial to inform your healthcare provider of any other medications you have recently taken before using Cialis or Viagra to avoid potential drug interactions.

Which Medication is Right for You?

Whether 20mg Cialis equals 100mg Viagra depends on your needs and preferences. If you value a longer duration of action and fewer food interactions, Cialis may be the better choice. On the other hand, if you prefer a shorter duration of action and are not concerned about potential side effects such as vision changes or rash, Viagra may be more suitable.

Ultimately, the choice between Cialis and Viagra should be made in consultation with your healthcare provider, who can assess your situation and recommend the most appropriate treatment for your needs.