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Cialis vs Viagra: Understanding the Differences

minute read

Written by: Duncan Reid

Man in bed with ED medicine in hand

Cialis and Viagra are both used to manage the symptoms of erectile dysfunction. While both medications are regularly prescribed to help men achieve and maintain an erection sufficient for sexual activity when sexually stimulated, there are several differences between the two, including when and how you take them, how long they last, and any potential side effects.

Erectile dysfunction is the inability to get or maintain an erection that is firm enough for sex. Neither Cialis nor Viagra will cause an erection on their own but both are designed to help you achieve and maintain your erection once aroused.  

Although erectile dysfunction is very common in men over the age of 40. Up to 50% of men under 50 experience erectile dysfunction. This means that erectile dysfunction can occur at any age. 

If you’re currently on Viagra or Cialis and looking to switch, or completely new to erectile dysfunction medication, this guide will give you all the information you need about each medication before you discuss which treatment is best for you with your doctor.

In this Article:

01: The history of Cialis and Viagra02: How to take Cialis and Viagra03: Cialis vs Viagra: What are the pros and cons?04: How do Cialis and Viagra side effects differ? 05: Why do Cialis and Viagra come in different doses? 06: Advice and information to help erectile dysfunction

The history of Cialis and Viagra

Viagra is a well-known brand name that contains the active ingredient sildenafil. Sildenafil was discovered by Pfizer in 1989 while looking for a treatment for high blood pressure and angina. Sildenafil was approved by the FDA in 1998 to treat erectile dysfunction. Viagra is a common household name as it is manufactured and sold by Pfizer. 

Cialis is the brand name for the active ingredient tadalafil. It wasn’t until 2003 that Cialis was approved in the US. Generic tadalafil became more widely available after 2018 when Eli Lilly and Company’s patent for Cialis expired.

How to take Cialis and Viagra

Both Cialis and Viagra come in tablet form and should be swallowed with a glass of water (but not grapefruit juice). You should limit your alcohol intake with both treatments to enjoy the greatest effects.

Cialis is faster acting than Viagra and can be taken in as little as 30 minutes before you plan to engage in sexual intercourse. You may also take Cialis with or without food. 

Viagra must be taken at least an hour before engaging in sexual intercourse. You must take Viagra on an empty stomach to get the best results. 

It’s common for men to not respond to erectile dysfunction treatment the first time they take it. You may take the tablet on eight separate occasions before speaking to your doctor about your results. Your doctor may then decide to switch your dose or form of treatment.

Cialis vs Viagra: What are the pros and cons?

Both medications can help men achieve and maintain an erection without one being more powerful than the other. The right treatment for you can depend on factors such as how often you have sex and whether you’d prefer the effects of the medication to last longer. 

A lower dose of Cialis can be prescribed to men that have sex at least 2-3 times per week. This is taken daily to enable spontaneous sexual activity. 

Viagra Connect is available without a doctor's prescription and can be bought after answering just a few simple questions online or in a pharmacy.

Pros of Cialis:

  • The effects last longer than Viagra

  • Unaffected by food intake

Cons of Cialis:

  • More expensive than Viagra

  • Can cause flushing, back pain, headaches, and muscle pain

Pros of Viagra:

  • Works for up to 82% of men 

  • Cheaper than Cialis

Cons of Viagra:

  • Effects don’t last as long as Cialis

  • Can cause vision changes, rashes and disorientation

How do Cialis and Viagra side effects differ?

As with any medication, Cialis and Viagra can cause side effects. Side effects can vary from common and uncommon to rare; some men will experience no side effects at all. 

Common Cialis side effects can include:

  • Headache

  • Back pain

  • Muscle aches

  • Pain in arms and legs 

  • Facial flushing

  • Nasal congestion 

  • Indegestion

Common Viagra side effects can include:

  • Headaches

  • Nausea

  • Facial flushing

  • Hot flush

  • Indigestion

  • Colour tinge to vision

  • Blurred vision

  • Visual disturbance

  • Stuffy nose

  • Dizziness 

Why do Cialis and Viagra come in different doses?

Cialis comes in strengths of 2.5mg, 5mg, 10mg and 20mg. 

Viagra comes in strengths of 25mg, 50mg and 100mg. 

The reason that Cialis comes in lower strengths is that Cialis can be taken as needed or daily. If taken for daily use, the strength of Cialis is prescribed at 2.5mg and 5mg.  

Viagra is taken on an as-needed basis, at an initial dosage of 50mg.

Erectile Dysfunction Medication: FAQs

Sildenafil is the active ingredient in Viagra. Tadalafil is the active ingredient in Cialis.

It is generally safe for most men to take erectile dysfunction medication. Erectile dysfunction medication is not suitable for everyone so you must speak to your doctor or pharmacist first.

Erectile dysfunction can be improved by maintaining a healthy weight, quitting smoking, cutting down your alcohol intake, exercising, and reducing stress.

Erectile dysfunction medicines

Advice and information to help erectile dysfunction