Viagra vs Cialis UK: Which ED Treatment Works Best?

Clinically Proven UK Registered Pharmacy

Viagra Tablet vs Cialis: Which Treatment Is Right for You?

UK-registered clinical team
Confidential and secure
No GP visit needed
Fast and discreet delivery
Start Your Free Consultation

Takes less than 2 minutes to complete 100% online

EDNEW 20% off for new customers
Genuine Products
UK-licensed only
Fast Delivery
Next-day available
Expert Advice
UK pharmacists
Man using Cured Pharmacy online consultation for erectile dysfunction treatment
From £0.45 Starting dose — clinically approved
LIVE PRICING

Our Pricing

Pricing Disclaimer: Prices on some pages may not be up to date — the live pricing table below and pricing shown during consultation are official current prices and take precedence over any other figures on the site.

Sildenafil - UK-licensed prescription Treatment
Treatment

Sildenafil

From £0.45

Future orders save 5%
Start Assessment
Tadalafil - UK-licensed prescription Treatment
Treatment

Tadalafil

From £9.99

Future orders save 5%
Start Assessment
Sildenafil Eropid - UK-licensed prescription Treatment
Treatment

Sildenafil Eropid

From £8.99

Future orders save 5%
Start Assessment
Tadalafil (Teva) - UK-licensed prescription Treatment
Treatment

Tadalafil (Teva)

From £9.99

Future orders save 5%
Start Assessment
Avarante Tablets Tadalafil Tablets 10mg - UK-licensed prescription Treatment
Treatment

Avarante Tablets Tadalafil Tablets 10mg

From £11.49

Future orders save 5%
Start Assessment
Viagra Connect 50mg - UK-licensed prescription Treatment
Treatment

Viagra Connect 50mg

From £11.49

Future orders save 5%
Start Assessment

Viagra Tablet vs Cialis: Which Treatment Is Right for You?

Published on: June 03, 2026

When comparing viagra tablet vs cialis uk comparison options, understanding the key differences helps you choose the most suitable erectile dysfunction treatment. Both medications are clinically proven phosphodiesterase-5 (PDE5) inhibitors licensed by the MHRA, but they differ significantly in onset time, duration of action, and dosing flexibility—factors that matter when matching treatment to your lifestyle and intimate relationship patterns.

How Viagra and Cialis Work: The Science Behind PDE5 Inhibitors

Viagra (sildenafil) and Cialis (tadalafil) both work by inhibiting the PDE5 enzyme, which breaks down cyclic guanosine monophosphate (cGMP) in the smooth muscle cells lining blood vessels in the penis [1]. When PDE5 is blocked, cGMP levels remain elevated, promoting smooth muscle relaxation and increased blood flow during sexual stimulation—the physiological mechanism required for achieving and maintaining an erection.

The critical distinction lies in their pharmacokinetic profiles. Sildenafil has a half-life of approximately 4 hours, meaning its concentration in the bloodstream reduces by half every 4 hours, whilst tadalafil's half-life extends to 17.5 hours—over four times longer [2]. This difference translates directly into duration of action: Viagra typically remains effective for 4-6 hours, whereas Cialis can maintain effectiveness for up to 36 hours, earning it the colloquial description as the 'weekend pill' among UK prescribers.

Both medications require sexual arousal to work—they facilitate the erectile response but do not create spontaneous erections. Clinical trials demonstrate that neither medication affects libido, fertility, or testosterone levels [1][2].

Viagra Tablet vs Cialis: Onset Time and Duration Compared

Viagra typically begins working within 30-60 minutes of ingestion, with peak plasma concentrations reached approximately 60 minutes after dosing on an empty stomach [1]. High-fat meals can delay absorption by up to 60 minutes, which is why UK prescribers often advise taking Viagra on an empty stomach or after a light meal for optimal results.

Cialis offers two distinct usage patterns. When taken as needed, tadalafil begins working within 30 minutes for some men, though the manufacturer recommends allowing up to 2 hours for full effect [2]. The extended 36-hour window means you don't need to time intimacy as precisely—a significant advantage for men who find the planning aspect of Viagra restrictive or anxiety-inducing.

For men who engage in sexual activity more than twice weekly, Cialis also comes in a daily low-dose formulation (2.5mg or 5mg), which maintains steady plasma levels and allows for spontaneous intimacy without timing considerations [3]. This daily regimen isn't suitable for everyone and requires prescriber assessment, but it represents a fundamentally different treatment approach compared to Viagra's on-demand model.

Which Timing Pattern Suits Your Lifestyle?

Men who prefer predictable, planned intimacy often find Viagra's shorter window sufficient and appreciate the medication clearing their system within 24 hours. Conversely, men in relationships with more spontaneous or frequent sexual activity typically benefit from Cialis's extended duration or daily dosing option. Your UK prescriber at Cured Pharmacy will discuss your relationship patterns during your free consultation to recommend the most appropriate treatment approach, subject to clinical suitability.

Effectiveness: Clinical Trial Data for Viagra and Cialis

In pivotal clinical trials, sildenafil demonstrated efficacy in approximately 70-85% of men with erectile dysfunction across various underlying causes, including diabetes, cardiovascular disease, and psychological factors [1]. The 100mg dose (the highest licensed strength) showed the greatest response rates, though many men achieve satisfactory results with 50mg—the recommended starting dose in the UK.

Tadalafil trials showed similar overall efficacy rates, with 68-81% of men reporting improved erections sufficient for sexual intercourse [2]. A key finding from head-to-head comparisons is that whilst both medications show comparable efficacy in controlled settings, patient preference studies consistently show higher satisfaction rates with tadalafil, primarily attributed to the reduced need for timing and the extended duration of action [4].

It's worth noting that 'effectiveness' encompasses more than just physiological response. In real-world UK practice, adherence and satisfaction often depend on how well the medication fits into a man's lifestyle. Clinical trials measure erection hardness and penetration success, but patient-reported outcomes consistently highlight that convenience, spontaneity, and reduced performance anxiety contribute significantly to treatment satisfaction [4].

Feature Viagra (Sildenafil) Cialis (Tadalafil)
Onset time 30-60 minutes 30 minutes to 2 hours
Duration of action 4-6 hours Up to 36 hours
Standard starting dose 50mg 10mg (on-demand)
Daily dosing option No Yes (2.5mg or 5mg)
Food interaction High-fat meals delay absorption Can be taken with or without food
Generic price at Cured Pharmacy From £0.45 From £9.99
Dosing frequency Once per 24 hours maximum Once per 24 hours (on-demand) or daily
Visual side effects Occasional (3% at 100mg) Rare
Back pain/muscle aches Uncommon More common (6-7%)

Side Effects: What to Expect from Viagra vs Cialis

Both medications share a similar side effect profile because they target the same PDE5 enzyme. The most commonly reported side effects include headache (occurring in 10-16% of users), facial flushing (10-13%), nasal congestion (4-10%), and indigestion (3-7%) [1][2]. These effects are generally mild to moderate and tend to diminish with continued use as the body adapts.

Sildenafil can occasionally cause temporary visual disturbances—a blue tinge to vision or increased light sensitivity—affecting approximately 3% of users at the 100mg dose [1]. This occurs because PDE5 is also present in the retina, and sildenafil has some cross-reactivity with PDE6, an enzyme involved in phototransduction. Tadalafil has lower affinity for PDE6 and rarely causes visual effects, but it shows slightly higher rates of back pain and muscle aches (affecting 6-7% of users), attributed to PDE11 inhibition in skeletal muscle [2].

Serious side effects are rare but require immediate medical attention. Priapism (an erection lasting more than 4 hours) occurs in fewer than 1 in 1,000 users but constitutes a medical emergency [1][2]. Both medications are contraindicated with nitrate medications (commonly prescribed for angina) due to risk of severe hypotension. Your UK prescriber will screen for these contraindications during your online consultation.

Managing Common Side Effects

Most men find side effects tolerable and temporary. Staying well-hydrated can reduce headache severity, whilst taking the medication with food (for Cialis) or after a light meal (for Viagra) may minimise indigestion. If side effects persist or become bothersome, your prescriber can adjust your dose or suggest switching between sildenafil and tadalafil, as individual tolerance varies. Never adjust your dose without consulting your prescriber.

Dosing Flexibility: Viagra Tablet vs Cialis Options

Viagra is available in three strengths: 25mg, 50mg, and 100mg tablets. The standard UK starting dose is 50mg, taken approximately one hour before sexual activity, with a maximum frequency of once per 24 hours [1]. If 50mg proves insufficient, your prescriber may increase to 100mg; if side effects are problematic, reduction to 25mg is appropriate. Sildenafil (the generic version of Viagra) offers identical active ingredient and efficacy at significantly lower cost—at Cured Pharmacy, sildenafil starts from £0.45 per tablet.

Cialis comes in 5mg, 10mg, and 20mg strengths for on-demand use, plus 2.5mg and 5mg for daily dosing [2]. The recommended starting dose for on-demand use is 10mg, taken at least 30 minutes before sexual activity, adjustable to 20mg if needed or reduced to 5mg if side effects occur. Daily Cialis (2.5mg or 5mg) is taken at the same time each day regardless of sexual activity timing, providing continuous readiness.

The generic tadalafil available at Cured Pharmacy from 20% offers the same clinical profile as branded Cialis but at considerably lower cost. All tadalafil and sildenafil products dispensed by Cured Pharmacy are UK-licensed and manufactured to MHRA standards, ensuring identical quality and safety to branded versions.

Cost Comparison: Viagra vs Cialis Pricing at UK Pharmacies

Generic sildenafil represents the most cost-effective erectile dysfunction treatment available in the UK, with prices at Cured Pharmacy starting from £0.45 per tablet—substantially lower than typical market rates for both generic and branded options. This makes sildenafil accessible for men who use the medication frequently or prefer to keep a supply available without significant ongoing expense.

Generic tadalafil pricing at Cured Pharmacy starts from 20% offering considerable savings compared to branded Cialis whilst delivering identical clinical efficacy. The higher per-tablet cost compared to sildenafil is offset by tadalafil's extended duration—one tablet potentially covers an entire weekend, whereas multiple sildenafil doses might be needed for the same period.

Branded Viagra Connect 50mg (the over-the-counter version) and prescription Cialis carry premium pricing, with Cialis starting from £0.45 at Cured Pharmacy. For most men, generic versions offer identical therapeutic benefit at a fraction of the cost. Your prescriber will discuss whether branded products offer any specific advantage in your situation, though in the vast majority of cases, generics represent optimal value without compromising treatment quality.

Understanding True Cost-Effectiveness

When comparing costs, consider usage patterns alongside per-tablet pricing. If you engage in sexual activity twice weekly, daily tadalafil might prove more cost-effective and convenient than on-demand dosing. Conversely, for occasional use, the lower per-tablet cost of sildenafil makes it economically advantageous. Cured Pharmacy displays transparent upfront pricing before your consultation, allowing you to compare options and make informed decisions about your treatment investment.

Scientific References

  1. Goldstein, I., Lue, T. F., Padma-Nathan, H., Rosen, R. C., Steers, W. D., & Wicker, P. A. (1998). Oral sildenafil in the treatment of erectile dysfunction. New England Journal of Medicine, 338(20), 1397-1404. https://doi.org/10.1056/NEJM199805143382001 [accessed 13 August 2026]
  2. Brock, G. B., McMahon, C. G., Chen, K. K., Costigan, T., Shen, W., Watkins, V., Anglin, G., & Whitaker, S. (2002). Efficacy and safety of tadalafil for the treatment of erectile dysfunction: results of integrated analyses. Journal of Urology, 168(4 Pt 1), 1332-1336. https://doi.org/10.1016/S0022-5347(05)64442-4 [accessed 13 August 2026]
  3. Porst, H., Giuliano, F., Glina, S., Ralph, D., Casabé, A. R., Elion-Mboussa, A., & Sorsaburu, S. (2006). Evaluation of the efficacy and safety of once-a-day dosing of tadalafil 5mg and 10mg in the treatment of erectile dysfunction: results of a multicenter, randomized, double-blind, placebo-controlled trial. European Urology, 50(2), 351-359. https://doi.org/10.1016/j.eururo.2006.02.052 [accessed 13 August 2026]
  4. Eardley, I., Mirone, V., Montorsi, F., Ralph, D., Kell, P., Warner, M., & Büttner, H. (2005). An open-label, multicentre, randomized, crossover study comparing sildenafil citrate and tadalafil for treating erectile dysfunction in men naïve to phosphodiesterase 5 inhibitor therapy. BJU International, 96(9), 1323-1332. https://doi.org/10.1111/j.1464-410X.2005.05794.x [accessed 13 August 2026]
  5. NHS. (2026). Erectile dysfunction (impotence). https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ Accessed 13 August 2026.

Information on this page is for educational purposes only and is not medical advice. All prescription treatments require clinical assessment by a UK-registered prescriber. Always consult a qualified healthcare professional before starting any new medication. Erectile dysfunction can sometimes indicate underlying cardiovascular conditions—if you experience chest pain, dizziness, or other concerning symptoms, seek immediate medical attention.

Trusted by thousands

Real people, real results

Jane L.

"Brilliant. Lost 4 stone on mounjaro no side effects at all. Cured pharmacy are excellent. Always helpful pens sent out quickly always comes with needles and sterile wipes. If you want to go on GLP-1 go to cured pharmacy. So professional. Thank you cured pharmacy you changed my health and well being."

Ann-Marie

"I absolutely love this product, I have been using 2.5mg as maintenance dose and have managed to control my weight without any side effects and can still eat well balanced meals. The pharmacy is very efficient friendly and helpful I would not purchase from anywhere else."

Sacha W.

"So far I'm really impressed by my results it's crazy cause I'm not snacking like how I used to do and I see my face slimming down already and it's only been 2 and a half weeks. Can't wait to give my feedback in 5 months time thank you cured pharmacy."

Kimberly G.

"Mounjaro has corrected my hormonal weight gain during menopause. I am using it now to maintain that balance. The results for me have been exceptional!"

Jennifer

"Great really helps cure those nasty habits can't wait for my next mounjaro pen."

How it Works?

Select from our recommended UK-licensed medications.

1

Choose your treatment

Step 1: Choose your treatment from Cured Pharmacy

Select safe UK treatments. Quick answers.

2

Answer quick questions

Step 2: Answer quick consultation questions

We will deliver direct to you as quickly as tomorrow.

3

Get it delivered fast

Step 3: Fast discreet delivery to your door

Start Your Assessment For Erectile Dysfunction

Start your journey to better health today.

  • Reviewed by UK-based prescribers
  • Takes under 3 minutes
  • Discreet Packaging

Start Your Journey To Better Health Today

Once you complete a short online assessment you will be able to choose your preferred treatment from safe medically approved options tailored to you.

Start My Assessment

Returning Customer?

Log in to Your Account

Faq

Which is better for first-time users: Viagra or Cialis?
Most UK prescribers recommend starting with sildenafil 50mg due to its shorter duration, allowing you to assess tolerability without extended side effects. If timing proves restrictive or you prefer longer duration, switching to tadalafil is straightforward after initial assessment.
Can I switch between Viagra and Cialis?
Yes, you can switch between sildenafil and tadalafil subject to prescriber approval. Many men try both to determine which suits their lifestyle and side effect profile better. Always complete a new consultation when switching medications.
Does Cialis work better than Viagra for severe erectile dysfunction?
Clinical trials show comparable efficacy rates for both medications across all severities of erectile dysfunction. Choice depends more on lifestyle fit than severity—neither medication is inherently 'stronger' when comparing equivalent doses.
How long does it take for Viagra tablet vs Cialis to start working?
Viagra typically works within 30-60 minutes, whilst Cialis can begin working from 30 minutes but may take up to 2 hours for full effect. Cialis's extended 36-hour window means precise timing is less critical than with Viagra's 4-6 hour duration.
Can I take Viagra and Cialis together?
No, you must never take sildenafil and tadalafil together or within 24 hours of each other. Both are PDE5 inhibitors, and combining them significantly increases the risk of serious side effects including dangerous drops in blood pressure.
Is generic sildenafil as effective as branded Viagra?
Yes, generic sildenafil contains the identical active ingredient at the same strength and is manufactured to the same MHRA standards as branded Viagra. Clinical effectiveness is equivalent, with generic options offering substantial cost savings.
Which lasts longer: Viagra or Cialis?
Cialis lasts significantly longer, remaining effective for up to 36 hours compared to Viagra's 4-6 hour window. This extended duration makes Cialis popular for weekend use and reduces the need for precise timing before intimacy.
Do I need a prescription for Viagra or Cialis in the UK?
Prescription-strength Viagra (sildenafil 100mg, 50mg, 25mg) and all Cialis (tadalafil) strengths require a prescription from a UK prescriber. Viagra Connect 50mg is available without prescription, but online pharmacies like Cured Pharmacy still require a clinical consultation to ensure safety and suitability.
Tarun Kumar, Prescribing Pharmacist

Medically reviewed by

Tarun Kumar, Prescribing Pharmacist (GPhC 2233073)

Reviewed on: June 03, 2026

Last reviewed: 13 August 2026

Last updated on 13 August 2026.

Review History

Our experts continually monitor new findings in health and medicine, and we update our articles when new information becomes available.

Why this page was updated on 13 August 2026

Content checked and updated as part of our periodic review, to ensure accuracy and currentness.

Current version (13 August 2026)

Edited by: The Editorial Team

Medically reviewed by:

Tarun Kumar, GPhC No. 2233073, Prescribing Pharmacist


How we source info.

When we present you with stats, data, opinion or a consensus, we'll tell you where this came from.