What’s the Best Cialis Dosage?

Medically reviewed by
Dr Brenda IkejiLast reviewed: 28 Feb 2025
What dosages are there, and which strength should you pick?
Cialis is a treatment for erectile dysfunction (ED) that works well for a lot of people. It contains the active ingredient tadalafil. Cialis comes in 4 different dosages, and some dosages can be taken daily.
If you need help finding the right dosage of Cialis, an online doctor or GP should be able to help. It’s a good idea to start with the 10 milligram (mg) tablet, which is the standard dosage. Just like with most medications, how well Cialis works can vary from person to person.

What are the dosages of Cialis?
Cialis Daily | Cialis On Demand | |
---|---|---|
Dosages (mg) | 2.5mg and 5mg |
10mg and 20mg |
When to take it | Every day |
Occasionally (when needed) |
Effectiveness | Get an erection anytime from 5 days of use |
Get an erection after 30 minutes (effects last for 36 hours) |
There are 4 dosages of Cialis:
- 2.5mg
- 5mg
- 10mg
- 20mg
The 2.5mg and 5mg options are called Cialis Daily, because you take this dosage once a day. This way, you can always be ready to get and keep erections easier.
The 10mg and 20mg dosages are called Cialis on demand because you don’t need to take them every day. Instead, you take them shortly before you want to be able to get an erection.
What are the differences between Cialis Daily and Cialis on demand?
Cialis Daily:
- 2.5mg and 5mg doses
- specifically designed for daily use
- should help you to get an erection from 5 days after you start taking it, every day
- will help you to get an erection at any time between taking doses
- can work well if you want an erectile dysfunction (ED) pill and want to able to get an erection at any time, without planning in advance
- the 2.5mg dosage is the most common one to start on
- the 5mg dosage is usually prescribed if you think you’ll want to get an erection at least twice a week
Cialis on demand:
- 10mg and 20mg doses
- effects last for up to 36 hours after each time you take a tablet
- this form of Cialis can work well if you don’t want to take a pill every day
- 10mg is usually the starting dose of Cialis on demand – it’s normally prescribed if you think you’ll want erections up to 2 days a week
- 20mg is the strongest Cialis dosage available – this is normally prescribed if you find that the 10mg dose isn’t strong enough for you
What dosage of Cialis should I take?
The right dosage for you may depend on how often you want to get an erection.
Up to twice a week
The 10mg and 20mg Cialis dosages are for occasional use, and ideal if you usually want to get an erection up to twice a week. You’ll be able to get an erection 30 to 60 minutes after you take a 10mg or 20mg dose.
Twice a week or more
Taking Cialis Daily builds up a steady amount of medication in your body. So the 2.5mg or 5mg daily dosages would be best if you want to be able to get an erection more than twice a week.
Is there a recommended dosage for Cialis?
Your doctor will typically prescribe the lower dosages of Cialis Daily or on-demand first to assess whether that will achieve the desired effect. If you’ve never taken it before, your recommended dosage for Cialis will be 10mg. This dose works well for a lot of people and has a lower chance of giving you side effects than the 20mg dosage. However, 20mg may be an option if the 10mg dosage doesn’t work for you.
What factors affect my dosage?
The Cialis dosage you will be prescribed by your doctor will depend on a number of factors. These typically include the following:
- your age and overall physical health
- how often you plan on being sexually active
- other medications you might be taking
- side effects you may develop from taking it
- how well the medication is working for you
Will I find a Cialis dosage that works for me?
Cialis isn’t right for everyone. Before you’re prescribed Cialis, you’ll need a consultation with a doctor. They’ll check your medical history to make sure Cialis wouldn’t interact with any other medications you’re taking, and you don’t have any medical conditions that make Cialis unsafe for you.
Your online doctor or GP may also be able to identify possible causes of your erectile dysfunction (ED). They’ll be able to advise on how to help tackle those causes.
How do I take Cialis?
Cialis is an oral medication, so you swallow it whole with water if needed. If you are taking a Cialis Daily dosage, you should aim to take it at the same time every day for best results. For Cialis on demand, take it at least 30 minutes or more before sexual activity. There is no need to eat before you take it, so it can be taken with or without food.
When should I switch dosages?
Switching because of side effects
If you experience side effects from Cialis, you can talk to your doctor about switching dosage.
Common side effects include:
- headaches
- redness (flushing)
- muscle and back pain
- acid reflux and indigestion
Less common side effects include:
- dizziness
- stomach ache
- heart racing, pounding, or fluttering (palpitations)
- more sweating than normal
- nosebleeds
- blurred vision
- painful eyes
- a higher heart rate than normal
In a medical emergency, call 999 and get medical attention as soon as you can.
Switching because your Cialis didn't work
You may also think about switching dose if you feel the dosage you’re taking isn’t working for you. If you’re taking the 10mg dose, your doctor might recommend moving to 20mg.
20mg is the strongest Cialis dosage. If this isn’t working for you, you won’t be able to increase it. Instead, it might be better for you to switch to a different ED medication.
What happens if I miss a dose?
If you forget to take your medication, follow these instructions if you have:
Cialis on demand – take it as soon as you remember, you’ll just need to wait until it starts working to have sex, but this could be a good time to engage in foreplay.
Cialis Daily – take your dose as soon as you remember but do not take a double dose to make up for a forgotten tablet. You should not take Cialis more than once a day so if you remember on the day your next dose is due, skip the missed dose.
Can I increase the dosage of Cialis if it doesn’t work for me?
If the dosage you’re taking isn’t working for you, your online doctor or GP might prescribe a higher dosage.
But, don’t just take more tablets of your current dosage. Taking Cialis more than the recommended dosage, could cause serious side effects.
How can I get the best results from my Cialis dosage?
There are a number of ways you can improve the effectiveness of Cialis, such as watching what you eat and avoiding alcohol before you take it.
Fatty foods
If you take Cialis with a meal, avoid high-fat foods which can affect how your body absorbs the Cialis.
Timing
Make sure you take:
- Cialis 10mg and 20mg around an hour before you want to get an erection – you won’t get an erection straight away
- 2.5mg and 5mg daily dosages at the same time every day
Cialis doesn’t cause erections directly – to get an erection with any erectile dysfunction (ED) medication, you need to be sexually aroused as normal. Take your time, and try to stay relaxed
Alcohol
Try to avoid drinking alcohol when you’re taking Cialis because it can:
- increase your heart rate
- reduce your blood pressure
- make headaches and dizziness more likely
- make it harder to get an erection and can cause you to lose the erection during sex
Grapefruit juice
Avoid drinking grapefruit juice because it can make Cialis slightly less safe.
How do Cialis dosages compare to other medications?
Cialis vs Viagra:
- the dosages of Viagra (sildenafil) and Cialis are different
- they also contain different active ingredients
- Cialis can last in the body for up to 36 hours, whereas Viagra may last up to 6 hours
- it can take both Viagra and Cialis up to an hour to work when taken as needed
There is no difference in dosage between branded Cialis and the generic version:
- Cialis and tadalafil have the same dosages available because they have the same active ingredient
- tadalafil is the active ingredient in Cialis
- tadalafil can be bought as a generic version of the drug
- the side effects of tadalafil and Cialis are the same
Conclusion
The dosages discussed in this article cover all the different ways you can take Cialis. You’ll always be started on the lowest dose whether you take it as needed or as a daily ED medication. You and your doctor will work together to find what Cialis dosage works best for you, so follow their advice for best results.
For your safety, do not adjust your dosage without speaking to a medical professional first. If you have questions about the effectiveness of your dosage, this should be raised directly with your doctor.

Brenda studied medicine at St Georges University of London and has most recently worked in John Radcliffe Oxford University Hospitals, covering acute and general medicine.
Meet our doctorsLast reviewed: 28 Feb 2025
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