Tried an ED medication and found it didn't do much? You're far from the only one. Erectile dysfunction (ED) medication doesn't work for everyone straight away, and there's often a reason behind it, whether that's how you're taking it, what else is going on with your health, or simply needing more than one attempt.
This guide covers the most common reasons ED medication isn't working, what's worth checking before you give up on it, and the other options available if tablets aren't the right fit for you.
A disappointing first try is common. It doesn't always mean treatment can't work for you.
How ED medication is meant to work
Erectile dysfunction, also called impotence, is when you struggle to get or keep an erection firm enough for sex.1 Occasional problems are common, especially in men over 40, and are often down to stress, tiredness or too much alcohol.1
Most ED tablets are PDE-5 inhibitors. They work by relaxing the blood vessels in your penis, so more blood can flow in when you're aroused. That's the part worth remembering: these medications do not create arousal on their own. You still need to be turned on for them to work.2
Timing and duration vary between the four main tablets:
- Sildenafil (Viagra) - usually taken around an hour before sex, and it can still help 4 to 5 hours later.2
- Tadalafil (Cialis) - can be taken as a one-off dose at least 30 minutes before sex, with benefits lasting up to 36 hours.3
- Vardenafil (Levitra) - usually taken around 25 to 60 minutes before sex, and it can still help 4 to 5 hours later.4
- Avanafil (Spedra) - usually taken around 15 to 30 minutes before sex.5
Think of these tablets as support, not a switch. You still need to feel turned on for anything to happen.
Common reasons your ED medication isn't working
If your ED medication hasn't worked the way you hoped, it's worth ruling a few things out before deciding it isn't for you. Our guide to common ED medication mistakes covers more of them.
Sometimes it's how or when the tablet is taken, rather than the medicine itself, that's holding it back.
You're not giving it enough time, or enough arousal
These tablets need sexual stimulation to work. No stimulation, no effect, however much you've taken.1 Give the tablet time to kick in, too. Sildenafil is usually taken about an hour before sex, and it can take longer to work if you've eaten a big meal beforehand.2
You've eaten a heavy meal
A heavy, fatty meal can slow down how quickly sildenafil and vardenafil are absorbed.2,4 Try taking your dose on an empty stomach or after a light meal, for the best chance of it working on time.
“ED tablets need sexual stimulation to work, so give them time to kick in. Conditions such as diabetes, high blood pressure and high cholesterol can cause ED, so mention them to your prescriber if a tablet hasn't worked. Do not increase your dose, take extra tablets or combine different tablets on your own.
Ana Carolina GoncalvesSuperintendent Pharmacist
You've only tried it once or twice
One disappointing attempt doesn't mean a medication won't work for you. Timing, food, alcohol and arousal can all get in the way, so it's worth checking them before you decide.
If a tablet still isn't working after a few tries, tell your prescriber exactly which medicine and dose you tried, how many times, and whether you had any side effects. They can decide what to do next, or whether you need a check-up with your GP. Do not increase your dose yourself.
You're on the wrong dose
Your prescriber can adjust your dose based on how well the tablet works and how well you tolerate it.2 They can only get it right if they know how you got on, so tell them if it hasn't worked.
Do not take extra tablets or change your dose on your own if it isn't working.
Something else could be getting in the way
A few other things can stop ED medication working as well as it should:
- An underlying health condition - diabetes, high blood pressure, high cholesterol and hormone problems can all cause ED.1 If tablets aren't helping, it's worth getting these checked. If it came on gradually alongside other symptoms like low energy or reduced libido, mention it to your GP, as hormone problems can cause ED. Our guide to ED and testosterone goes into this in more depth.
- Other medications - some medicines can cause ED as a side effect.1 Alpha-blockers (used for prostate problems or high blood pressure) can also interact with ED tablets.2 Always tell your prescriber about everything else you're taking.
- Stress, anxiety or relationship worries - ED tablets will not resolve performance anxiety or relationship stress by themselves. If this feels like the bigger issue, ask your GP about counselling or sex therapy, alongside or instead of medication.1
- Alcohol and grapefruit juice - drinking too much alcohol can make it harder to get an erection.1,6 Grapefruit juice can raise the levels of these medicines in your body and make side effects more likely, so it's best avoided.7,2
ED that doesn't respond to tablets can be an early sign of another health condition, so it's worth getting checked.
Other options if tablets aren't right for you
If you've ruled out the common causes and your ED medication still isn't giving you the result you want, there are other options worth discussing with your prescriber.
Tablets aren't the only route. If they haven't worked for you, ask your prescriber what else might suit you.
Tadalafil Daily
Rather than taking a tablet each time, Tadalafil Daily is a low dose taken at about the same time every day.7,8 It's an option for men who expect to use ED treatment at least twice a week.8
Steady levels build up over about 5 days, so it won't work straight away.8 You still need to be sexually stimulated for it to work. Do not add on-demand tadalafil or another ED medicine unless your prescriber has given you a specific plan.8
Vacuum pump
A vacuum pump, such as the VaxAid Deluxe, encourages blood to flow into the penis, which causes an erection. It's a non-medical option that can be used if medicine isn't suitable or doesn't work, although it isn't always available on the NHS.1
Alprostadil injection or cream
If tablets aren't suitable, or haven't worked, alprostadil is another prescription option. It comes as an injection into the side of the penis, or as a cream applied to the tip of the penis.9,10 Do not use it together with ED tablets, as the combination can cause erections that last too long.9 Pharmica doesn't supply alprostadil, so speak to your GP or a specialist about whether either form is appropriate for you.
Lifestyle changes that can help
Your day-to-day habits can play a part in ED, and small changes may help.1
Eat well. NHS advice for ED includes eating a healthy diet and losing weight if you're overweight.1
Move more. Regular exercise is part of the NHS advice too.1
Watch how much you cycle. Cycling for more than 3 hours a week has been linked to erection problems in some men, so it's worth a mention if you're a keen cyclist.1
Quit smoking. Stopping smoking is part of the NHS advice for ED.1
Cut back on alcohol. Drinking too much can make erections harder to get. The NHS advises not drinking more than 14 units a week.1
Small changes add up, and even one or two of these habits is a good place to start.
When should you see a GP?
Speak to a GP or pharmacist if:
- Your ED medication still is not working after several attempts, even with your prescriber adjusting the dose or timing
- Your erection problems started suddenly, or alongside other symptoms like low energy or reduced libido
- You take nitrates for angina or chest pain, or riociguat (a medicine for high blood pressure in the lungs). Do not take ED tablets with nitrates, poppers or riociguat, as combining them can cause a dangerous drop in blood pressure.6,2 Do not combine ED tablets, take an extra dose or change your dose yourself, and ask your prescriber to review your other medicines.
- You get an erection that lasts longer than 4 hours. This needs urgent medical attention.6
Never take ED tablets with nitrates, poppers or riociguat, and do not combine different ED tablets.
If you bought ED medication without a prescription, such as Cialis Together, it's also worth having a GP check-up within 6 months. ED can be linked to other health conditions, such as diabetes or high blood pressure.11,1
Frequently asked questions
Why isn't my ED medication working?
There are a few possible reasons: you might not be giving it enough time or arousal, you could have eaten a heavy meal beforehand, your dose may need adjusting by your prescriber, or an underlying health condition or other medication could be getting in the way. Checking your timing and arousal, and reviewing your dose with your prescriber, can help.
How many times should I try ED medication before deciding it doesn't work?
There's no set number of tries that suits everyone. One attempt isn't always a fair test, as timing, food, alcohol and arousal can all get in the way. If it still isn't working after a few tries taken as prescribed, tell your prescriber which medicine and dose you tried and how many times. Do not increase your dose yourself.
Can I take ED medication with alcohol?
It's best to keep alcohol to a minimum around the time you take it. Drinking too much can make it harder to get an erection, and alcohol can make dizziness more likely with tadalafil.
Is it safe to take ED medication if I have high blood pressure or diabetes?
It depends. Diabetes and high blood pressure are common causes of ED, and treatment needs to be prescribed with your health history and other medicines in mind. Always tell your prescriber about any existing conditions and medications you're taking.
Can I take ED medication with nitrates?
No. Do not take ED tablets with nitrate medicines, poppers or riociguat, as combining them can cause a dangerous drop in blood pressure. Speak to your GP or pharmacist if you're unsure whether this applies to you.
What if ED medication doesn't work for me at all?
If you've ruled out timing, dose and lifestyle factors and it's still not working, there are other options such as Tadalafil Daily, a vacuum pump, or alprostadil injections or cream. Your prescriber or GP can help you find the right fit.
References
- NHS. Erection problems (erectile dysfunction). NHS; 2023. nhs.uk
- Viatris. Viagra 50 mg film-coated tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2025. medicines.org.uk/emc
- Eli Lilly and Company Limited. Cialis 10mg film-coated tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2026. medicines.org.uk/emc
- Zentiva Pharma UK Limited. Vardenafil Zentiva 10 mg film-coated tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2025. medicines.org.uk/emc
- A. Menarini Farmaceutica Internazionale. Spedra 100 mg tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2024. medicines.org.uk/emc
- NHS. Sildenafil (Viagra): a medicine for erection problems. NHS; 2026. nhs.uk
- NHS. Tadalafil. NHS; 2026. nhs.uk
- Eli Lilly and Company Limited. Cialis 5mg film-coated tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2026. medicines.org.uk/emc
- Pfizer Limited. Caverject 10 micrograms powder for solution for injection: Summary of Product Characteristics. Electronic Medicines Compendium; 2024. medicines.org.uk/emc
- The Simple Pharma Company Limited. Vitaros 3 mg/g cream: Summary of Product Characteristics. Electronic Medicines Compendium; 2023. medicines.org.uk/emc
- Opella Healthcare UK Limited. Cialis Together 10 mg tablets: Summary of Product Characteristics. Electronic Medicines Compendium; 2025. medicines.org.uk/emc
This article is intended for informational purposes only and does not replace professional medical advice. Always read the patient information leaflet supplied with your medication and speak to a healthcare professional if you have specific concerns.