Vardenafil and Paxlovid: Can You Take Them Together?

Takes less than 2 minutes to complete 100% online

What is vardenafil and how does it work?

Vardenafil (the generic version of Levitra) is a prescription medicine used to treat erectile dysfunction in men [5]. It belongs to a group of medicines called PDE5 inhibitors, which work by relaxing blood vessels in the penis, allowing increased blood flow when you are sexually aroused [1].

Vardenafil is available in 5 mg, 10 mg, and 20 mg tablets and is usually taken about 25 to 60 minutes before sexual activity [5]. The effect can last for several hours, but you should not take more than one dose in 24 hours. Like all PDE5 inhibitors, vardenafil requires sexual stimulation to work—it will not cause an erection on its own [2].

Your body breaks down vardenafil using an enzyme system called CYP3A4, mainly in the liver. Any medicine that affects this enzyme system can change how much vardenafil stays in your bloodstream, which is why drug interactions need careful checking before you start treatment [5].

What is Paxlovid and when is it used?

Paxlovid is an antiviral medicine used to treat COVID-19 in adults who do not need supplemental oxygen and who are at increased risk of developing severe illness [12]. It contains two active ingredients: nirmatrelvir (which stops the virus from multiplying) and ritonavir (which boosts nirmatrelvir levels in the blood).

Ritonavir is a very potent inhibitor of the CYP3A4 enzyme system—the same system your body uses to break down vardenafil and other PDE5 inhibitors [12]. This means that while you are taking Paxlovid, many other medicines will stay in your system much longer than usual, leading to higher levels and a greater risk of side effects.

A course of Paxlovid typically lasts five days. During this time, your prescriber or pharmacist will review all your current medicines to identify any that might interact, and they may advise pausing, adjusting, or switching certain treatments temporarily [12]. Because ritonavir's effect on drug metabolism is so strong, even a short course can have significant interactions.

When to get urgent help

• Erection lasting more than four hours (priapism)—go to A&E immediately
• Sudden loss of vision or hearing—stop vardenafil and seek same-day medical advice
• Severe dizziness, fainting, or chest pain—call 999 or go to A&E
• Symptoms of a severe allergic reaction (swelling of face, lips, or throat, difficulty breathing)—call 999

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

How do vardenafil and Paxlovid interact?

Vardenafil and Paxlovid interact because the ritonavir component of Paxlovid dramatically slows the breakdown of vardenafil in your liver [5]. This can lead to much higher levels of vardenafil in your bloodstream, even from a normal dose, which increases the risk of side effects such as headache, flushing, dizziness, visual disturbances, and—more seriously—a dangerous drop in blood pressure.

According to the British National Formulary, vardenafil is contraindicated (should not be used) with potent CYP3A4 inhibitors, including ritonavir-boosted regimens like Paxlovid [5]. This means that during a course of Paxlovid, you should avoid taking vardenafil altogether. The interaction is considered too significant to manage safely with dose adjustment alone.

If you are prescribed Paxlovid and you currently use vardenafil for erectile dysfunction, your prescriber will advise you to stop vardenafil for the duration of the Paxlovid course (usually five days) and for a short period afterwards to allow the ritonavir to clear from your system [12]. This temporary pause helps keep you safe from the interaction.

Why the interaction matters

The interaction between vardenafil and Paxlovid is not just theoretical—it has real clinical significance. Excessive levels of vardenafil can cause a severe drop in blood pressure, especially if you are also taking other medicines that lower blood pressure, such as alpha-blockers or antihypertensives [5]. Symptoms might include severe dizziness, fainting, or even cardiovascular complications.

Because Paxlovid is prescribed for COVID-19, you may already be unwell, which makes managing side effects more difficult. Your prescriber will always weigh the benefit of treating your COVID infection against the risk of drug interactions, and in this case, pausing vardenafil for a few days is a straightforward and safe solution [12].

What your prescriber checks before treatment

Before prescribing vardenafil, your clinician will ask about all the medicines you currently take, including prescription drugs, over-the-counter treatments, herbal supplements, and any recent courses of antibiotics or antivirals [2]. This review is essential to identify interactions like the one with Paxlovid.

If you are starting Paxlovid while already using vardenafil, your doctor or pharmacist will advise you to stop the vardenafil temporarily. They will also check whether you are taking any other medicines that interact with ritonavir, as the list is extensive and includes treatments for heart disease, high cholesterol, mental health conditions, and more [12].

Your prescriber will also review your cardiovascular health, blood pressure, and any history of heart attack, stroke, or severe liver or kidney problems, because these factors affect whether PDE5 inhibitors like vardenafil are safe for you in general [2][5]. At Cured Pharmacy, every prescription for vardenafil follows an online consultation reviewed by a UK-registered prescriber, ensuring that all interactions and contraindications are checked before treatment is approved.

Declaring all your medicines

It is vital to declare every medicine you take during your consultation, even if you think it is unrelated to erectile dysfunction. Some interactions are not obvious—for example, you might not realise that an antibiotic or antifungal you were prescribed a few weeks ago could still affect how your body handles vardenafil [5].

If you are prescribed Paxlovid by your GP or hospital, tell them immediately that you use vardenafil or any other PDE5 inhibitor. Similarly, if you are considering starting ED treatment and you have recently had COVID-19 or taken Paxlovid, mention this during your consultation so your prescriber can advise on safe timing [12].

At a glance

Practical advice if you need both medicines

If you are prescribed Paxlovid and you currently use vardenafil, the safest approach is to pause your vardenafil for the duration of the Paxlovid course (five days) and for at least two to three days afterwards [12]. Ritonavir can remain in your system and continue to affect drug metabolism for a short time after you finish the course.

Do not take vardenafil while you are on Paxlovid, even at a reduced dose, unless your prescriber has given you specific alternative advice. The contraindication is clear, and the risk of serious side effects outweighs the benefit of continuing ED treatment for a few days [5].

Once you have completed Paxlovid and allowed a washout period, you can safely resume vardenafil at your usual dose. If you have any concerns or experience symptoms such as severe dizziness, chest pain, or an erection lasting more than four hours, seek urgent medical advice [1][5]. Remember that erectile dysfunction treatment is important, but managing an acute infection like COVID-19 takes priority, and a short break from vardenafil will not affect your long-term treatment plan.

Alternative ED treatments during Paxlovid

If you need to pause vardenafil during a course of Paxlovid, you might wonder whether other erectile dysfunction treatments are safer. Unfortunately, all oral PDE5 inhibitors—including sildenafil (Viagra), tadalafil (Cialis), and avanafil (Spedra)—are affected by ritonavir to varying degrees [3][4][6].

Sildenafil and tadalafil may be used at reduced doses with potent CYP3A4 inhibitors in some circumstances, but this requires careful prescriber assessment and is not routinely recommended during a short Paxlovid course [3][4]. Avanafil, like vardenafil, is contraindicated with potent inhibitors [6]. The simplest and safest option is to pause all oral PDE5 inhibitors while taking Paxlovid.

Non-oral treatments such as Eroxon gel (a topical medical device available without prescription) do not have the same drug interaction concerns, as they work locally rather than being absorbed into the bloodstream in significant amounts [12]. If you need ED support during your Paxlovid course, discuss this option with your pharmacist. Once your antiviral treatment is complete, you can return to your usual oral ED medicine.

Resuming treatment safely

After finishing Paxlovid, wait at least two to three days before restarting vardenafil to allow ritonavir to clear from your system [12]. If you are unsure about the timing, contact your prescriber or pharmacist for personalised advice—they can take into account your kidney and liver function, which affect how quickly medicines are eliminated.

When you do resume vardenafil, start with your usual prescribed dose unless your prescriber advises otherwise. There is no need to reduce the dose once the interaction has cleared. If you experience any unexpected side effects or your ED treatment does not work as well as before, speak to your clinician, as your overall health or other medicines may have changed [2][5].

In summary

• Do not take vardenafil while on Paxlovid—ritonavir raises vardenafil levels and increases side-effect risk
• Pause vardenafil for the five-day Paxlovid course plus two to three days afterwards
• All oral PDE5 inhibitors interact with Paxlovid; topical options like Eroxon may be used short-term
• Always declare all medicines during your consultation so interactions can be checked
• Resume vardenafil at your usual dose once Paxlovid has cleared from your system

Frequently Asked Questions