Tadalafil and Fampridine: Can They Be Taken Together?
Learn about the interaction, safety checks, and what your prescriber needs to know.
Takes less than 2 minutes to complete 100% online
Tadalafil and Fampridine: Understanding the Interaction
Published: 21 October 2026
Many men prescribed fampridine for multiple sclerosis wonder whether tadalafil and fampridine can be taken together safely. The good news is that no major interaction between these two medicines is commonly reported in clinical practice, but your prescriber will still need to review your full medication list and medical history during the consultation. This page explains what each medicine does, how they might interact, and the safety checks that take place before tadalafil is prescribed.
At a glance
What is tadalafil and fampridine used for?
Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor licensed in the UK to treat erectile dysfunction (ED) in men [4]. It works by relaxing blood vessels in the penis, allowing increased blood flow when you are sexually aroused. Tadalafil is available as on-demand tablets (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 option (2.5 mg or 5 mg) [4]. It is the active ingredient in branded Cialis and generic versions.
Fampridine (also known as dalfampridine outside the UK) is a potassium channel blocker used to improve walking ability in adults with multiple sclerosis (MS) [12]. It is marketed as Fampyra in the UK and works by helping nerve signals travel more effectively along damaged nerve fibres. Fampridine does not treat ED and is taken twice daily for its neurological benefits. Because MS can affect sexual function, some men taking fampridine may also seek treatment for erectile difficulties.
Is there an interaction between tadalafil and fampridine?
No major interaction between tadalafil and fampridine is commonly reported in the medical literature or national drug databases [3][4][12]. The two medicines work through different mechanisms in different parts of the body: tadalafil acts on blood vessels primarily in the penis, while fampridine affects nerve conduction in the central nervous system. They are not known to interfere with each other's metabolism or increase the risk of serious side effects when used together.
However, it is important to understand that the absence of a commonly reported interaction does not mean the combination is automatically suitable for everyone. Your prescriber will check your full medication list, including fampridine, during the online consultation to ensure there are no individual risk factors. Fampridine itself can occasionally cause side effects such as dizziness or urinary tract infections, and your prescriber will consider your overall health picture before approving tadalafil.
How the prescriber checks for safety
When you request tadalafil through Cured Pharmacy, a UK-registered prescriber reviews your medical questionnaire, which asks about all current medicines, health conditions, and recent symptoms. The prescriber will specifically check for medicines that are known to interact dangerously with tadalafil—such as nitrates, nicorandil, riociguat, or other PDE5 inhibitors—and will also look at medicines that may require dose adjustments, such as alpha-blockers or potent CYP3A4 inhibitors [3][4]. Fampridine will be noted, and the prescriber will confirm that the combination is appropriate for your individual circumstances.
What your prescriber needs to know about tadalafil and fampridine
During your consultation, you must declare that you are taking fampridine and provide details of the dose and how long you have been on it. The prescriber will also ask about your MS symptoms, any recent changes in your condition, and whether you take any other medicines for MS or other health problems. This information helps the prescriber assess whether tadalafil is suitable and whether any dose adjustments are needed.
It is equally important to mention any other medicines you take, including over-the-counter products, herbal remedies (such as St John's wort), and recreational substances. For example, alpha-blockers used for prostate symptoms can interact with tadalafil and require a lower starting dose [4]. Potent CYP3A4 inhibitors, such as certain antifungals or HIV medicines, can raise tadalafil levels and necessitate dose restrictions [4]. Never take tadalafil with nitrates, nicorandil, riociguat, or alkyl nitrites ('poppers'), as this combination can cause a dangerous drop in blood pressure [4].
What you need to know
- No major interaction between tadalafil and fampridine is commonly reported in clinical practice.
- Declare all medicines, including fampridine, during your online consultation for a full safety review.
- Never take tadalafil with nitrates, nicorandil, riociguat, or poppers—this can be life-threatening.
- Continue fampridine as prescribed; do not stop or change any medicine without medical advice.
- Seek urgent help for an erection lasting over four hours or sudden vision or hearing loss.
Practical advice for taking tadalafil and fampridine together
If your prescriber approves tadalafil, take it exactly as directed. On-demand tadalafil (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 the same time, allowing for spontaneity. Continue taking fampridine as prescribed by your neurologist—do not stop or change the dose without medical advice. Both medicines can be taken with or without food, though a large, high-fat meal may delay the absorption of tadalafil slightly.
Be aware of how each medicine might make you feel. Fampridine can occasionally cause dizziness, and tadalafil may also cause dizziness or headache, especially when you first start [4][12]. Avoid heavy alcohol, as it can worsen erectile difficulties and add to the blood-pressure-lowering effect of tadalafil. If you experience any new or unusual symptoms after starting tadalafil—such as severe dizziness, chest pain during sex, or an erection lasting more than four hours—seek medical help immediately.
Monitoring and follow-up
Keep in touch with both your GP or neurologist (who manages your MS and fampridine) and the prescriber who oversees your tadalafil. If your fampridine dose changes, or if you start any new medicine, inform the prescriber before your next tadalafil order. Regular check-ins help ensure that your treatment remains safe and effective. If tadalafil does not work as expected, or if you develop side effects, the prescriber can adjust the dose or suggest an alternative PDE5 inhibitor, such as sildenafil or vardenafil.
Other medicines that interact with tadalafil and fampridine
While tadalafil and fampridine do not interact with each other in a clinically significant way, each medicine has its own list of potential interactions. For tadalafil, the most serious interactions are with nitrates (GTN spray, isosorbide mononitrate or dinitrate), nicorandil, riociguat, and alkyl nitrites—these combinations can cause a life-threatening drop in blood pressure and must never be taken together [4]. Alpha-blockers (such as doxazosin or tamsulosin) can also lower blood pressure when combined with tadalafil, so patients must be stable on the alpha-blocker and start tadalafil at the lowest dose [4].
Potent CYP3A4 inhibitors, including ritonavir, cobicistat, ketoconazole, itraconazole, and clarithromycin, can raise tadalafil levels, requiring dose reductions [4]. CYP3A4 inducers like rifampicin, carbamazepine, phenytoin, and St John's wort can make tadalafil less effective. Fampridine has fewer drug interactions, but it should be used cautiously with other medicines that lower the seizure threshold or affect kidney function [12]. Your prescriber will review all these factors during the consultation.
When to get urgent help
- Erection lasting more than 4 hours (priapism)—go to A&E immediately
- Sudden loss of vision or hearing—seek urgent medical attention
- Chest pain during sexual activity—stop and call 999
- Severe dizziness, fainting, or allergic reaction (rash, swelling, breathing difficulty)—call 999
- New or worsening MS symptoms—contact your neurologist or GP promptly
Call 999 or go to A&E in an emergency, or contact NHS 111 for urgent advice.
When to seek medical advice about tadalafil and fampridine
Seek urgent medical help if you experience an erection lasting more than four hours (priapism), sudden loss of vision or hearing, or chest pain during sexual activity while taking tadalafil [4]. These are rare but serious side effects that require immediate attention. If you develop severe dizziness, fainting, or an allergic reaction (rash, swelling, difficulty breathing), call 999 or go to A&E.
Contact your GP or prescriber promptly if you notice new symptoms after starting tadalafil, such as persistent headache, flushing, indigestion, or back pain that does not settle. If your MS symptoms change or worsen, or if your neurologist adjusts your fampridine dose or adds a new medicine, let your tadalafil prescriber know before your next order. Never stop taking fampridine or any other prescribed medicine without discussing it with your doctor first. Erectile dysfunction can sometimes be an early sign of cardiovascular disease or diabetes, so if you have not already done so, see your GP for a full health check [1][2].
How Cured Pharmacy can help
Cured Pharmacy is a GPhC-registered online pharmacy (GPhC 9012511) offering discreet, convenient access to ED treatments after a clinical consultation with a UK-registered prescriber. You complete a short online questionnaire, and a prescriber reviews your answers, including all current medicines such as fampridine, to ensure tadalafil is safe for you. If approved, your medicine is dispensed by our pharmacy and delivered in plain, unmarked packaging. We stock a range of tadalafil options, from affordable generics to branded Cialis, so you can choose the treatment that suits your needs and budget.
Declare all your medicines
Always list fampridine and every other medicine you take during your online consultation. This allows the prescriber to check for interactions and ensure tadalafil is safe for you.
Scientific References
- NHS. (n.d.). Erectile dysfunction (impotence). NHS website. https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ [accessed 21 October 2026]
- National Institute for Health and Care Excellence. (n.d.). Erectile dysfunction. Clinical Knowledge Summaries. https://cks.nice.org.uk/topics/erectile-dysfunction/ [accessed 21 October 2026]
- Joint Formulary Committee. (n.d.). Sildenafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/sildenafil/ [accessed 21 October 2026]
- Joint Formulary Committee. (n.d.). Tadalafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/tadalafil/ [accessed 21 October 2026]
- Electronic Medicines Compendium. (n.d.). Summaries of Product Characteristics and Patient Information Leaflets. https://www.medicines.org.uk/emc/ [accessed 21 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
Start Your Journey To Better Health Today
Once you complete a short online assessment you will be able to choose your preferred treatment from safe medically approved options tailored to you.
Start My Assessment Log in to Your AccountED Treatments We Offer
Pricing Disclaimer: Prices on some pages may not be up to date — the live pricing table below and pricing shown during consultation are official current prices and take precedence over any other figures on the site.
Trusted by thousands
Real people, real results
“Fabulous service and quick delivery”
“Felt the effects of these after about 5 days. Erections are better and can get aroused and ready easier”
“Excellent value and brilliant customer service”
“I received excellent service and everything went well. The order arrived quickly and in perfect condition. It's working very well! Thank you to the whole team for the great work!”
“Delivery was good, the product lived up to expectations.”
How Our Online Service Works
Choose your treatment
Select from our recommended UK-licensed medications.
Answer quick questions
Select safe UK treatments. Quick answers.
Get it delivered fast
We will deliver direct to you as quickly as tomorrow.
Your Questions Answered
Can I take tadalafil if I am on fampridine for multiple sclerosis?
No major interaction between tadalafil and fampridine is commonly reported, but you must declare fampridine during your online consultation so the prescriber can review your full medication list and medical history.
Will fampridine make tadalafil less effective?
There is no evidence that fampridine reduces the effectiveness of tadalafil. The two medicines work through different mechanisms and are not known to interfere with each other.
Do I need to stop fampridine before starting tadalafil?
No, you should continue taking fampridine exactly as prescribed by your neurologist. Do not stop or change any prescribed medicine without medical advice.
What should I tell my prescriber about my MS medication?
List all medicines you take for MS, including fampridine, baclofen, gabapentin, or any other treatments, along with doses and how long you have been on them. This helps the prescriber assess safety.
Are there any MS medicines that cannot be taken with tadalafil?
Most MS medicines do not have major interactions with tadalafil, but the prescriber checks every current medicine during the consultation. Never take tadalafil with nitrates, nicorandil, or riociguat.
Can tadalafil cause side effects if I am on fampridine?
Both medicines can occasionally cause dizziness. Your prescriber will assess whether the combination is suitable for you and advise on what to watch for.
How long does tadalafil last, and how often can I take it?
On-demand tadalafil (10 mg or 20 mg) can last up to 36 hours and should not be taken more than once a day. Daily tadalafil (2.5 mg or 5 mg) is taken once daily at the same time.
What should I do if I start a new medicine while taking tadalafil and fampridine?
Inform your tadalafil prescriber before your next order if your neurologist changes your fampridine dose or adds a new medicine, so they can check for any new interactions.
Medically reviewed by
Tarun Kumar, Superintendent Pharmacist (GPhC 2233073)