Tadalafil and Rizatriptan: Can You Take Them Together?

Tadalafil and Rizatriptan: Understanding the Interaction

Published: 25 October 2026

Many men wonder whether tadalafil and rizatriptan can be taken together, especially if they use tadalafil for erectile dysfunction and rizatriptan for migraines. The good news is that no major direct interaction between these two medicines is commonly reported in clinical practice, but there are important safety considerations your prescriber will check. This page explains what each medicine does, how they might affect each other, and the practical steps to use them safely.

What Is Tadalafil and How Does It Work?

Tadalafil is a prescription medicine used to treat erectile dysfunction (ED) in men [3][4]. It belongs to a group of medicines called PDE5 inhibitors, which work by relaxing the blood vessels in the penis, allowing more blood to flow in when you are sexually aroused. Tadalafil does not cause an erection on its own—sexual stimulation is still needed for it to work [1].

Tadalafil is available in two forms: on-demand tablets (usually 10mg or 20mg taken at least 30 minutes before sex, with effects lasting up to 36 hours) and daily tablets (2.5mg or 5mg taken once a day) [4]. The long duration of action is why tadalafil is sometimes called the 'weekend pill'. Common brand names include Cialis, and generic versions are widely available at lower cost.

Because tadalafil lowers blood pressure slightly as part of its action, it can interact with other medicines that also affect blood pressure or are broken down by the same liver enzymes [4]. This is why your prescriber will always review your full medication list, including any medicines you take for other conditions such as migraines.

What Is Rizatriptan and How Does It Work?

Rizatriptan is a prescription medicine used to treat migraine headaches [12]. It belongs to a class of medicines called triptans, which work by narrowing blood vessels around the brain and blocking pain pathways. Rizatriptan is usually taken as soon as a migraine starts, and it can help relieve headache, nausea, and sensitivity to light and sound.

Rizatriptan is available as standard tablets (usually 10mg) or wafers that dissolve on the tongue (5mg or 10mg), making it convenient to take without water. It typically starts working within 30 minutes to 2 hours. Like tadalafil, rizatriptan can affect blood vessels, though it works in a different way—triptans cause blood vessels in the brain to narrow, whereas tadalafil causes blood vessels in the penis to widen [12].

Because rizatriptan affects blood vessels and can occasionally cause chest tightness or changes in blood pressure, your prescriber will want to know about all your other medicines, including those for erectile dysfunction. This ensures that the combination is safe for your individual circumstances.

The Interaction Between Tadalafil and Rizatriptan

No major direct interaction between tadalafil and rizatriptan is commonly reported in standard drug interaction databases or clinical practice. These two medicines work through different mechanisms—tadalafil inhibits the PDE5 enzyme to improve blood flow to the penis, while rizatriptan acts on serotonin receptors to narrow blood vessels in the brain during a migraine [4][12]. They are not known to interfere with each other's breakdown in the liver or to cause dangerous effects when used together.

However, both medicines can affect the cardiovascular system in different ways. Tadalafil lowers blood pressure slightly, while rizatriptan can occasionally cause chest tightness, palpitations, or changes in blood pressure in some people [12]. For most men, this combination does not cause problems, but your prescriber will assess your individual heart health and blood pressure before approving both medicines together.

It is important to declare all your medicines—including over-the-counter treatments and supplements—during your online consultation. Your prescriber will check for any personal risk factors (such as heart disease, high blood pressure, or previous stroke) that might make the combination less suitable for you. Never assume a combination is safe without professional advice, even if no major interaction is listed.

Why Your Prescriber Checks Your Full Medical History

When you request tadalafil and rizatriptan, your prescriber will review your cardiovascular health, blood pressure, and any history of heart disease or stroke. Both medicines can affect blood vessels, so it is essential to ensure your heart and circulation are healthy enough for sexual activity and that rizatriptan is safe for your migraine pattern [1][2]. Your prescriber will also check whether you take any other medicines that could interact with either tadalafil or rizatriptan, such as other migraine treatments, blood pressure tablets, or antidepressants. This thorough review helps ensure the combination is safe and appropriate for you.

What Your Prescriber Will Check Before Approving Tadalafil and Rizatriptan

During your online consultation, your prescriber will ask about your cardiovascular health, including any history of heart attack, stroke, angina, or heart failure. Tadalafil is not suitable if sexual activity is inadvisable due to heart problems, and rizatriptan should be used with caution in people with certain cardiovascular conditions [4][12]. Your prescriber will also check your current blood pressure and whether you take any medicines that lower blood pressure, as adding tadalafil could increase the risk of dizziness or fainting.

You will be asked about all your current medicines, including other migraine treatments (such as ergotamine or other triptans), antidepressants (especially SSRIs or MAOIs), and any medicines for high blood pressure or prostate problems. Your prescriber will also check whether you use nitrates, nicorandil, riociguat, or 'poppers' (amyl nitrite), as these are absolutely contraindicated with tadalafil and can cause a dangerous drop in blood pressure [3][4].

Finally, your prescriber will review your migraine pattern and frequency. If you have very frequent migraines or take rizatriptan more than a few times a week, this may need further investigation by your GP. Similarly, if your erectile dysfunction is new or worsening, your prescriber may recommend seeing your GP, as ED can be an early sign of heart disease or diabetes [1][2].

Practical Advice for Taking Tadalafil and Rizatriptan Safely

If your prescriber approves both medicines, take each one exactly as directed. For on-demand tadalafil, take your dose at least 30 minutes before planned sexual activity (effects can last up to 36 hours). For daily tadalafil, take one tablet at the same time each day [4]. For rizatriptan, take it as soon as a migraine starts—do not wait for the headache to become severe. You can take rizatriptan and tadalafil on the same day if needed, as there is no major interaction, but always follow the dosing instructions for each medicine.

Be aware of side effects from each medicine. Tadalafil can cause headache, indigestion, back pain, flushing, or nasal congestion [4]. Rizatriptan can cause dizziness, drowsiness, dry mouth, or a tingling sensation [12]. If you experience chest pain, severe dizziness, or an unusually fast or irregular heartbeat after taking either medicine, stop and seek medical advice immediately. Do not take more than the prescribed dose of either medicine, and do not take rizatriptan more than twice in 24 hours.

Avoid heavy alcohol when using tadalafil, as it can worsen erectile dysfunction and increase the risk of dizziness or low blood pressure [4]. Grapefruit juice can raise tadalafil levels in your blood, so it is best avoided. If you develop a new health condition, start a new medicine, or notice any unusual symptoms, contact your prescriber or GP before continuing with either tadalafil or rizatriptan.

When to Seek Urgent Medical Help

Seek immediate medical help (call 999 or go to A&E) if you experience chest pain or tightness during or after sex, as this could indicate a heart problem [1]. Also seek urgent help if you have an erection lasting more than 4 hours (priapism), sudden loss of vision or hearing, or severe dizziness or fainting [3][4]. If you have a severe migraine that is different from your usual pattern, sudden severe headache (especially if it feels like a 'thunderclap'), or weakness or numbness on one side of your body, call 999 immediately, as these could be signs of a stroke.

Other Medicines and Interactions to Be Aware Of

While tadalafil and rizatriptan do not have a major direct interaction, both medicines can interact with other treatments. Tadalafil must never be taken with nitrates (such as GTN spray, isosorbide mononitrate, or isosorbide dinitrate), nicorandil, riociguat, or 'poppers' (amyl or alkyl nitrites), as the combination can cause a dangerous fall in blood pressure [3][4]. Do not take tadalafil with another PDE5 inhibitor (such as sildenafil or vardenafil) at the same time.

Rizatriptan should not be taken with ergotamine or other triptans on the same day, and it should be used with caution if you take certain antidepressants (such as SSRIs, SNRIs, or MAOIs) due to a risk of serotonin syndrome [12]. If you take an alpha-blocker for prostate problems (such as tamsulosin or doxazosin), your prescriber will ensure you are stable on that medicine before starting tadalafil, and you will usually start on the lowest dose of tadalafil to reduce the risk of dizziness [4].

Potent CYP3A4 inhibitors (such as ritonavir, ketoconazole, itraconazole, or clarithromycin) can raise tadalafil levels, so your prescriber may reduce your tadalafil dose if you take these medicines [4]. CYP3A4 inducers (such as rifampicin, carbamazepine, phenytoin, or St John's wort) can make tadalafil less effective. Always declare every medicine, supplement, and herbal remedy you use during your consultation, and never stop or change a prescribed medicine without advice from your prescriber or GP.

How Cured Pharmacy Can Help

Cured Pharmacy is a GPhC-registered online pharmacy (GPhC 9012511) offering a convenient, confidential service for erectile dysfunction treatments. After you complete an online consultation, a UK-registered prescriber will review your answers, check for interactions with your current medicines (including rizatriptan), and approve the most suitable treatment if it is safe for you. Your medicine is then dispensed by our pharmacy team and delivered discreetly to your door. If you have any questions about taking tadalafil with rizatriptan or any other medicine, our pharmacists are here to help—just contact us through your account or by phone.

Scientific References

1. NHS. (n.d.). Erectile dysfunction (impotence). NHS website. https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ [accessed 25 October 2026]
2. National Institute for Health and Care Excellence. (n.d.). Erectile dysfunction. Clinical Knowledge Summaries. https://cks.nice.org.uk/topics/erectile-dysfunction/ [accessed 25 October 2026]
3. Joint Formulary Committee. (n.d.). Sildenafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/sildenafil/ [accessed 25 October 2026]
4. Joint Formulary Committee. (n.d.). Tadalafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/tadalafil/ [accessed 25 October 2026]
5. Electronic Medicines Compendium. (n.d.). Summaries of Product Characteristics and Patient Information Leaflets. https://www.medicines.org.uk/emc/ [accessed 25 October 2026]

Information on this page is for educational purposes only and is not medical advice. Prescription treatments require clinical assessment by a UK-registered prescriber. Always consult a qualified healthcare professional before starting or changing any medication.

Get Treatment in 3 Steps

1

Choose your treatment

Select from our recommended UK-licensed medications.

2

Answer quick questions

Select safe UK treatments. Quick answers.

3

Get it delivered fast

We will deliver direct to you as quickly as tomorrow.