Tadalafil and Dexamfetamine: Can You Take Them Together?

Takes less than 2 minutes to complete 100% online

Tadalafil and Dexamfetamine: Understanding the Interaction

Published: 20 October 2026

If you're prescribed dexamfetamine for ADHD and considering tadalafil for erectile dysfunction, you may wonder whether tadalafil and dexamfetamine can be taken together safely. The good news is that no major direct interaction between these two medicines is commonly reported in clinical practice. However, both medicines can affect your cardiovascular system in different ways, so your prescriber will carefully check your heart health, blood pressure, and overall medical history before approving treatment.

What is Tadalafil and How Does It Work?

Tadalafil is a prescription medicine used to treat erectile dysfunction (ED) in men. 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 [3][4]. Tadalafil does not cause an erection on its own—sexual stimulation is still needed.

Tadalafil is available in two main forms: on-demand tablets (usually 10mg or 20mg) taken at least 30 minutes before sexual activity, with effects lasting up to 36 hours, and daily low-dose tablets (2.5mg or 5mg) for men who prefer spontaneity [4]. The longer duration of action is why tadalafil is sometimes called the 'weekend pill'.

Common brand names include Cialis, but generic tadalafil is widely available and just as effective. At Cured Pharmacy, tadalafil is available from £7.95 after a consultation with a UK-registered prescriber, who will check your medical history and current medicines to ensure it is safe and suitable for you.

What is Dexamfetamine and Why is It Prescribed?

Dexamfetamine (also spelled dexamphetamine) is a central nervous system stimulant prescribed mainly for attention deficit hyperactivity disorder (ADHD) and, less commonly, for narcolepsy. It works by increasing the levels of certain neurotransmitters—dopamine and noradrenaline—in the brain, which helps improve focus, attention, and impulse control.

Because dexamfetamine is a stimulant, it can raise your heart rate and blood pressure, particularly when you first start taking it or if the dose is increased. This is why people taking dexamfetamine have their blood pressure and heart rate monitored regularly by their prescriber.

Dexamfetamine is a controlled medicine in the UK, reflecting its potential for misuse and the need for careful medical supervision. If you have been prescribed dexamfetamine, it is essential to tell any doctor or pharmacist about it when seeking treatment for other conditions, including erectile dysfunction.

Can ADHD Medication Affect Erectile Function?

Some men taking stimulant medications for ADHD, including dexamfetamine, report changes in sexual function. Stimulants can sometimes reduce libido or make it harder to achieve or maintain an erection, though this does not affect everyone. The reasons are not fully understood but may relate to the effects on blood flow, neurotransmitter balance, or psychological factors such as anxiety. If you have noticed changes in your sexual health since starting ADHD medication, it is worth discussing this with your GP or prescriber, as they may be able to adjust your treatment or explore other options.

Tadalafil and Dexamfetamine: Is There a Direct Interaction?

There is no well-documented direct pharmacological interaction between tadalafil and dexamfetamine—they work on different systems in the body and are not known to interfere with each other's metabolism or effectiveness. Tadalafil is broken down mainly by the liver enzyme CYP3A4, while dexamfetamine does not significantly affect this enzyme.

However, both medicines can influence your cardiovascular system. Dexamfetamine can increase heart rate and blood pressure, while tadalafil can cause a small drop in blood pressure due to its blood-vessel-relaxing effects [4]. In most healthy men, these changes are mild and well tolerated, but your prescriber will need to assess your individual cardiovascular health before approving the combination.

It is crucial to be honest during your online consultation about all medicines you are taking, including dexamfetamine, so the prescriber can check for any risks specific to you. They may ask about your blood pressure readings, any heart conditions, and how well controlled your ADHD treatment is. Never take tadalafil without declaring your current medications, as this could put your health at risk.

What Your Prescriber Will Check Before Approving Tadalafil

When you request tadalafil through Cured Pharmacy's online consultation, a UK-registered prescriber will review your medical history and current medicines carefully. If you are taking dexamfetamine, they will pay particular attention to your cardiovascular health, including your blood pressure, heart rate, and any history of heart problems or stroke [2].

The prescriber will also check that you are not taking any medicines that are absolutely contraindicated with tadalafil. These include nitrates (such as GTN spray or isosorbide mononitrate), nicorandil, riociguat, and recreational drugs known as 'poppers' (amyl or alkyl nitrites). Do not take tadalafil together with any of these medicines, as the combination can cause a dangerous drop in blood pressure [3][4].

If you are on other blood-pressure medicines or alpha-blockers (such as tamsulosin or doxazosin), the prescriber will ensure you are stable on those treatments and may recommend starting tadalafil at a lower dose. They will also ask about your general health, including any history of priapism (prolonged erections), eye problems such as NAION (sudden vision loss), or severe liver or kidney disease. This thorough assessment ensures that tadalafil is both safe and likely to be effective for you.

Starting on the Lowest Effective Dose

If you are taking dexamfetamine and your prescriber approves tadalafil, they may suggest starting with the lowest effective dose—often 10mg on-demand or 2.5mg daily—to see how your body responds. This cautious approach helps minimise any potential side effects, such as dizziness or headache, and allows you to assess whether the treatment works for you. You should never increase the dose or take tadalafil more frequently than recommended without consulting your prescriber first.

Practical Advice for Taking Tadalafil and Dexamfetamine Safely

If your prescriber has approved the combination of tadalafil and dexamfetamine, there are some practical steps you can take to use both medicines safely and effectively. First, take each medicine exactly as prescribed—do not adjust doses or timings on your own. Dexamfetamine is usually taken in the morning or early afternoon to avoid sleep problems, while on-demand tadalafil is taken at least 30 minutes before sexual activity [4].

Monitor how you feel, especially when you first start tadalafil. Some men experience mild side effects such as headache, flushing, indigestion, or nasal congestion. These are usually temporary and improve as your body adjusts. However, if you notice dizziness, light-headedness, or a rapid or irregular heartbeat, sit or lie down and contact your GP or prescriber for advice.

Avoid drinking large amounts of alcohol when taking tadalafil, as alcohol can worsen erectile dysfunction and increase the risk of low blood pressure and dizziness. Grapefruit juice can also raise tadalafil levels in your blood, so it is best to avoid it. Stay well hydrated, and if you have any concerns or new symptoms, do not hesitate to seek medical advice. Remember, sexual activity itself can put strain on your heart, so if you experience chest pain during sex, stop immediately and seek urgent help.

When to Seek Medical Help and Warning Signs to Watch For

While most men tolerate tadalafil well, even when taking other medicines like dexamfetamine, it is important to know the warning signs that require urgent medical attention. If you develop an erection that lasts longer than four hours (priapism), you must go to A&E immediately, as this can cause permanent damage to the penis if not treated promptly [3][4].

Sudden loss of vision in one or both eyes, or sudden decrease or loss of hearing (sometimes with ringing in the ears or dizziness), are rare but serious side effects that require you to stop taking tadalafil and seek medical help straight away [4]. Similarly, if you experience chest pain, severe dizziness, or fainting during or after sexual activity, call 999 or go to A&E.

If you notice any new or worsening symptoms after starting tadalafil—such as palpitations, shortness of breath, or swelling of the ankles—contact your GP or prescriber as soon as possible. Never ignore symptoms or try to manage them on your own. It is also important not to stop or change your dexamfetamine or any other prescribed medicine without advice from your doctor, as this could affect your ADHD control or overall health. Open communication with your healthcare team is key to safe and effective treatment.

Reporting Side Effects

If you experience any side effects while taking tadalafil, whether or not they are listed in the patient information leaflet, you can report them via the UK Yellow Card Scheme at yellowcard.mhra.gov.uk or by searching for 'Yellow Card' in the Google Play or Apple App Store. Reporting side effects helps improve the safety information available for all patients.

Scientific References

1. National Institute for Health and Care Excellence. (n.d.). Erectile dysfunction. Clinical Knowledge Summaries. https://cks.nice.org.uk/topics/erectile-dysfunction/ [accessed 20 October 2026]
2. Joint Formulary Committee. (n.d.). Sildenafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/sildenafil/ [accessed 20 October 2026]
3. Joint Formulary Committee. (n.d.). Tadalafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/tadalafil/ [accessed 20 October 2026]
4. NHS. (n.d.). Erectile dysfunction (impotence). https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ Accessed 20 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 Discreet ED Treatment Online

Start your journey to better health today.

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