Vardenafil and Nicorandil: Can They Be Taken Together?

Vardenafil and Nicorandil: Understanding the Interaction

Published: 2 November 2026

Vardenafil and nicorandil must never be taken together. This combination can cause a dangerous and potentially life-threatening drop in blood pressure. Nicorandil is a heart medicine used to prevent and treat angina, while vardenafil is a prescription treatment for erectile dysfunction (ED). Both medicines affect blood vessels, and taking them together creates a serious safety risk that cannot be managed by adjusting doses or timing.

What Is Vardenafil and How Does It Work?

Vardenafil (also known by the brand name Levitra) is a prescription medicine used to treat erectile dysfunction in men. It belongs to a group of medicines called PDE5 inhibitors, which work by relaxing blood vessels in the penis, allowing increased blood flow when a man is sexually aroused [5].

Vardenafil is typically taken about 25 to 60 minutes before sexual activity, and its effects can last for several hours. It is available in 5mg, 10mg, and 20mg tablets. The medicine does not cause an erection on its own—sexual stimulation is still needed for it to work [5].

Common side effects include headache, flushing, nasal congestion, and indigestion. Like all PDE5 inhibitors, vardenafil also lowers blood pressure slightly as part of its normal action. This blood-pressure effect is usually mild and well-tolerated in healthy men, but it becomes dangerous when combined with certain other medicines, including nicorandil [5].

What Is Nicorandil and Why Is It Prescribed?

Nicorandil is a prescription medicine used to prevent and treat angina (chest pain caused by reduced blood flow to the heart). It is often prescribed for people with coronary heart disease, particularly when other angina medicines have not been fully effective or are not suitable.

Nicorandil works in two ways: it opens up (dilates) blood vessels, reducing the workload on the heart, and it also activates potassium channels in the heart muscle, which helps protect the heart during periods of reduced oxygen supply. This dual action makes it useful for managing angina symptoms and reducing the frequency of angina attacks.

Because nicorandil dilates blood vessels throughout the body, it lowers blood pressure. This effect is beneficial for heart health but creates a serious interaction risk when combined with medicines that also lower blood pressure—particularly PDE5 inhibitors like vardenafil. The combination can lead to a severe and uncontrolled drop in blood pressure, which can cause fainting, shock, heart attack, or stroke.

How Nicorandil Affects Blood Pressure

Nicorandil's blood-vessel-widening effect is similar in some ways to that of nitrate medicines (such as GTN spray or isosorbide mononitrate), which are also absolutely contraindicated with PDE5 inhibitors. While nicorandil is not technically a nitrate, it shares the same dangerous interaction profile. The blood-pressure-lowering effects of nicorandil and vardenafil add together unpredictably, and there is no safe way to manage this combination through dose adjustment or timing.

Why Vardenafil and Nicorandil Must Not Be Taken Together

The interaction between vardenafil and nicorandil is classified as an absolute contraindication, meaning these two medicines must never be used together under any circumstances. Both medicines dilate blood vessels and lower blood pressure, and when combined, their effects multiply in a way that can cause blood pressure to fall to dangerously low levels [5].

This severe drop in blood pressure (hypotension) can lead to dizziness, fainting, loss of consciousness, heart attack, stroke, or even death. The risk cannot be reduced by taking the medicines at different times of day, lowering the dose, or any other precaution. If you are taking nicorandil for angina, vardenafil is not a safe option for treating erectile dysfunction.

This contraindication applies to all PDE5 inhibitors, not just vardenafil. Sildenafil (Viagra), tadalafil (Cialis), and avanafil (Spedra) are also absolutely contraindicated with nicorandil for the same reason. The British National Formulary and the medicines' official prescribing information make this restriction clear, and UK prescribers are required to check for nicorandil use before prescribing any PDE5 inhibitor [3][4][5][6].

What Your Prescriber Will Check Before Prescribing Vardenafil

Before prescribing vardenafil or any other ED medicine, a UK prescriber must carry out a thorough assessment of your medical history and current medicines. This assessment is a legal and clinical requirement designed to keep you safe. You will be asked about any heart conditions, blood pressure problems, recent heart attacks or strokes, and all medicines you are currently taking—including prescription medicines, over-the-counter products, and herbal supplements.

The prescriber will specifically check whether you are taking any nitrates (such as GTN spray, isosorbide mononitrate, or isosorbide dinitrate), nicorandil, riociguat (a medicine for pulmonary hypertension), or any other PDE5 inhibitor. If you are taking any of these, vardenafil will not be prescribed. The prescriber will also review other medicines that may interact, such as alpha-blockers for prostate problems, blood pressure medicines, and certain antibiotics or antifungals [5].

It is essential to answer these questions honestly and completely. If you are taking nicorandil, the prescriber will discuss alternative options for managing erectile dysfunction that do not carry the same interaction risk. Never withhold information about your medicines or medical conditions in the hope of obtaining a prescription—doing so could put your life at risk.

Declaring All Your Medicines

Many people take medicines prescribed by different doctors or purchased over the counter, and it can be easy to forget to mention everything. Make a list of all your current medicines, including their names and doses, before starting your consultation. Include any herbal remedies (such as St John's wort), vitamins, and supplements. If you use GTN spray or tablets for angina—even if only occasionally—you must declare this, as it is also absolutely contraindicated with vardenafil.

Safe Alternatives for Erectile Dysfunction if You Take Nicorandil

If you are taking nicorandil for angina, oral PDE5 inhibitors (vardenafil, sildenafil, tadalafil, and avanafil) are not safe options. However, erectile dysfunction is a common and treatable condition, and there are alternative approaches that may be suitable depending on your individual circumstances and overall health [1][2].

Non-oral prescription treatments include Vitaros, an alprostadil cream applied to the tip of the penis, and Caverject, an alprostadil injection. These work locally rather than affecting blood vessels throughout the body, so they do not have the same interaction with nicorandil. However, they still require a prescription and a full medical assessment, as they are not suitable for everyone [7].

Eroxon is a topical gel medical device available without prescription. It works by creating a cooling then warming sensation that stimulates blood flow locally. Vacuum erection devices are another non-drug option. Your GP or a specialist can also discuss psychological support, lifestyle changes (such as increasing physical activity, losing weight if needed, reducing alcohol, and stopping smoking), and treating any underlying causes of ED, such as diabetes or high cholesterol [1][2].

It is important to have an open conversation with your GP about your angina treatment and erectile dysfunction. In some cases, your heart medicine regimen may be reviewed to see if an alternative to nicorandil is appropriate, though this decision must be made by your cardiologist or GP based on your heart health. Never stop or change your angina medicine without medical advice, as this could put your heart at risk.

Recognising Warning Signs and When to Seek Urgent Help

If you have accidentally taken vardenafil and nicorandil together, or if you experience symptoms of very low blood pressure after taking any ED medicine, you need urgent medical help. Symptoms of dangerously low blood pressure include severe dizziness, feeling faint or lightheaded, blurred vision, confusion, nausea, cold or clammy skin, rapid or weak pulse, and loss of consciousness. Call 999 or go to A&E immediately if you experience any of these symptoms.

Other warning signs that require urgent medical attention include chest pain during or after sexual activity (stop the activity and call 999), an erection lasting more than four hours (priapism, which requires emergency treatment to prevent permanent damage), sudden loss of vision in one or both eyes, or sudden decrease or loss of hearing, possibly with ringing in the ears. These are rare but serious side effects of PDE5 inhibitors that need immediate assessment [5].

If you are unsure whether a medicine you are taking might interact with vardenafil, do not guess. Contact your GP, pharmacist, or the prescribing service before taking any ED medicine. At Cured Pharmacy, every prescription request is reviewed by a UK-registered prescriber who will check your medical history and current medicines to ensure any treatment is safe for you. All prescription ED medicines are supplied only after this clinical assessment has been completed.

What to Do If You Miss Information During Your Consultation

If you realise after your consultation that you forgot to mention nicorandil or any other important medicine or medical condition, contact the pharmacy or prescribing service immediately before taking the ED medicine. It is always better to delay treatment and provide complete information than to risk a dangerous interaction. The clinical team can review your case and advise on the safest way forward.

Scientific References

1. NHS. (n.d.). Erectile dysfunction (impotence). NHS website. https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ [accessed 2 November 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 2 November 2026]
3. Joint Formulary Committee. (n.d.). Sildenafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/sildenafil/ [accessed 2 November 2026]
4. Joint Formulary Committee. (n.d.). Tadalafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/tadalafil/ [accessed 2 November 2026]
5. Joint Formulary Committee. (n.d.). Vardenafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/vardenafil/ [accessed 2 November 2026]
6. Joint Formulary Committee. (n.d.). Avanafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/avanafil/ [accessed 2 November 2026]
7. Joint Formulary Committee. (n.d.). Alprostadil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/alprostadil/ [accessed 2 November 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.