Tadalafil and Mesalazine: Can You Take Them Together?

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Key takeaways

• No major interaction is commonly reported between tadalafil and mesalazine
• Always declare all medicines including IBD treatments during your consultation
• Your prescriber reviews your full medical history to ensure tadalafil is safe
• Never take tadalafil with nitrates, nicorandil, riociguat or poppers
• Seek urgent help for erections lasting over 4 hours or sudden vision or hearing loss

What is tadalafil and mesalazine used for?

Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor licensed in the UK to treat erectile dysfunction (ED) [4]. It works by relaxing blood vessels in the penis, allowing increased blood flow when you are sexually aroused. Tadalafil is available as an on-demand treatment (10 mg or 20 mg taken at least 30 minutes before sex, with effects lasting up to 36 hours) or as a daily low-dose tablet (2.5 mg or 5 mg) [4]. Tadalafil is the active ingredient in branded Cialis and is also available as a generic medicine.

Mesalazine (also called mesalamine or 5-aminosalicylic acid) is an anti-inflammatory medicine used to treat and maintain remission in ulcerative colitis and Crohn's disease [12]. It works locally in the gut to reduce inflammation. Mesalazine is available in various formulations—tablets, granules, suppositories and enemas—designed to release the active ingredient at different points in the digestive tract. Brand names include Asacol, Pentasa, Salofalk, Mezavant and Octasa.

Both medicines are prescription-only in the UK. If you have inflammatory bowel disease (IBD) and are experiencing erectile dysfunction, it is important to discuss both conditions with your healthcare team, as chronic illness and some IBD symptoms can affect sexual function and quality of life [1].

Is there an interaction between tadalafil and mesalazine?

No clinically significant interaction between tadalafil and mesalazine is commonly reported in the medical literature or prescribing databases [4][12]. Mesalazine works locally in the bowel and is only partially absorbed into the bloodstream, so it does not usually interfere with the way tadalafil is processed by the body. Tadalafil is broken down mainly by liver enzymes (CYP3A4), and mesalazine does not significantly affect these enzymes.

However, it is essential to remember that your prescriber will review your complete medication list during your consultation. This includes all prescription medicines, over-the-counter products, herbal supplements and recreational substances. Even when no major interaction is expected, your medical history—such as heart conditions, blood pressure, kidney or liver function—will influence whether tadalafil is safe and appropriate for you [2].

If you are taking mesalazine for inflammatory bowel disease, you may also be on other medicines such as corticosteroids, immunosuppressants (azathioprine, mercaptopurine) or biological therapies. You must declare all of these during your consultation so your prescriber can assess the overall picture and ensure there are no concerns.

At a glance

What your prescriber checks before prescribing tadalafil

When you request tadalafil through Cured Pharmacy, a UK-registered prescriber will review your online consultation answers to ensure the treatment is safe for you [2]. They will check your current medicines (including mesalazine and any other IBD treatments), your medical history, and whether you have any conditions that make PDE5 inhibitors unsuitable.

Key safety checks include whether you take nitrates (GTN spray, isosorbide mononitrate or dinitrate), nicorandil, riociguat or recreational drugs called 'poppers' (amyl or alkyl nitrites). You must never take tadalafil with any of these, as the combination can cause a dangerous drop in blood pressure [4]. Your prescriber will also ask about alpha-blockers (such as tamsulosin or doxazosin), blood pressure medicines, and potent CYP3A4 inhibitors like ritonavir, ketoconazole or clarithromycin, which can raise tadalafil levels and require dose adjustments [4].

You will be asked about heart conditions, recent heart attack or stroke, very low blood pressure, severe liver or kidney disease, and any history of sudden vision or hearing loss. Sexual activity itself places demands on the heart, so your prescriber must confirm that it is safe for you to be sexually active [2]. If you have not seen your GP about erectile dysfunction yet, you should do so, as ED can be an early warning sign of cardiovascular disease or diabetes [1].

Declaring your full medication list

Always list every medicine you take, including mesalazine, any other IBD treatments, vitamins, herbal supplements and recreational drugs. Even if you think a medicine is unrelated to ED, your prescriber needs the complete picture to make a safe decision. Do not stop or change any prescribed medicine without consulting your doctor or pharmacist first.

Practical advice for taking tadalafil with mesalazine

If your prescriber approves tadalafil, you can take it alongside mesalazine without special timing restrictions. Tadalafil on-demand tablets (10 mg or 20 mg) should be taken at least 30 minutes before sexual activity, and the effect can last up to 36 hours [4]. Daily tadalafil (2.5 mg or 5 mg) is taken once a day at roughly the same time, regardless of when you plan to have sex. Mesalazine is usually taken two to three times a day with or after food, depending on the formulation your doctor has prescribed.

You do not need to separate the doses of tadalafil and mesalazine. However, if you experience diarrhoea or other bowel symptoms that affect how well you absorb medicines, speak to your IBD team, as this may influence the effectiveness of your mesalazine. Tadalafil is absorbed in the upper digestive tract and is less likely to be affected by lower bowel inflammation, but severe diarrhoea or vomiting could reduce absorption of any oral medicine.

Avoid drinking large amounts of alcohol when taking tadalafil, as alcohol can worsen erectile dysfunction and add to the blood-pressure-lowering effect, increasing the risk of dizziness or fainting [4]. Grapefruit juice can raise tadalafil levels in the blood, so it is best to avoid it. If you feel dizzy or light-headed after taking tadalafil, sit or lie down until the feeling passes, and do not drive or operate machinery.

Managing inflammatory bowel disease and erectile dysfunction

Living with a chronic condition like IBD can affect your confidence, energy and sexual health. Fatigue, pain, anxiety about symptoms and the emotional impact of a long-term illness can all contribute to erectile dysfunction [1]. Speak openly with your GP or IBD specialist nurse about any sexual health concerns—they can offer support, review your medicines, and refer you to specialist services if needed. Treating ED effectively can improve your quality of life and relationship satisfaction.

Warning signs and when to seek urgent help

Tadalafil is generally well tolerated, but you should be aware of rare but serious side effects that require urgent medical attention. If you develop an erection that lasts longer than four hours (priapism), go to A&E immediately or call 999. Priapism can damage the penis permanently if not treated promptly [4].

Seek urgent help if you experience sudden loss of vision in one or both eyes, which could be a sign of non-arteritic anterior ischaemic optic neuropathy (NAION), a rare but serious condition [4]. Similarly, sudden decrease or loss of hearing, sometimes with ringing in the ears or dizziness, requires immediate medical assessment. If you develop chest pain during or after sexual activity, stop and seek medical help—do not take nitrate medicines (such as GTN spray) if you have used tadalafil in the past 48 hours, as this combination is dangerous [4].

Common side effects of tadalafil include headache, indigestion, back pain, muscle aches, flushing and nasal congestion [4]. These are usually mild and temporary. If you experience severe or persistent side effects, contact your prescriber or pharmacist for advice. For mesalazine, watch for new or worsening abdominal pain, bloody diarrhoea, fever or signs of an allergic reaction, and contact your IBD team or GP if these occur.

How to order tadalafil and mesalazine safely from Cured Pharmacy

Cured Pharmacy is a GPhC-registered online pharmacy (GPhC 9012511) offering a range of erectile dysfunction treatments, including tadalafil, after a clinical consultation reviewed by a UK-registered prescriber. To request tadalafil, complete the online questionnaire honestly and in full, listing all your current medicines—including mesalazine and any other treatments for inflammatory bowel disease—as well as your medical history and any allergies.

A UK prescriber will review your answers to ensure tadalafil is safe and suitable for you. If approved, your medicine will be dispensed by our pharmacy team and delivered discreetly to your home. Tadalafil (generic Cialis) is available from £7.95, or £6.36 for first orders using code Ednew. We also stock branded Cialis, Avarante (tadalafil), and other ED treatments including sildenafil (generic Viagra), vardenafil (generic Levitra) and Spedra (avanafil). All prices include the prescriber consultation and delivery.

If you have any questions about taking tadalafil with mesalazine or any other medicine, our pharmacist-led team is here to help. You can contact us through the website or by phone. Remember, never stop or change a prescribed medicine without speaking to your doctor or pharmacist first, and always see your GP if you have new or worsening erectile dysfunction, as it can be an early sign of other health conditions [1][2].

Why choose Cured Pharmacy for ED treatment?

Cured Pharmacy combines clinical expertise with convenience and discretion. Every prescription is reviewed by a UK-registered prescriber, and our team of experienced pharmacists is available to answer your questions. We offer genuine UK-licensed medicines at transparent prices, with fast, discreet delivery. Your health and safety are our priority, and we are here to support you at every step.

When to get urgent help

• Erection lasting longer than 4 hours (priapism) – go to A&E or call 999 immediately
• Sudden loss of vision in one or both eyes – seek urgent medical help
• Sudden decrease or loss of hearing, with or without ringing in the ears or dizziness
• Chest pain during or after sexual activity – stop and seek medical help; do not take nitrates
• Severe allergic reaction (rash, swelling of face or throat, difficulty breathing) – call 999

Call 999 or go to A&E in an emergency, or contact NHS 111 for urgent advice.