Tadalafil interactions: what to avoid and why
Tadalafil interactions can cause dangerous low blood pressure with nitrates and some other drugs. Review key combinations and when to get urgent help.
Key facts
- Tadalafil Daily is $129/month (billed $387 every 90 days), charged only after a clinician approves it.
- Answer a few health questions online. A licensed clinician reviews them. If approved, it ships to your door.
- Adults 18 or older. A licensed clinician reviews your health history and decides whether treatment is appropriate for you. Availability depends on the state you live in.
Tadalafil is a PDE5 inhibitor used for erectile dysfunction and other conditions. The main safety issue is tadalafil interactions that can drop your blood pressure too low, especially with certain heart and lung medicines. If you are sorting out symptoms like erectile dysfunction or medication side effects, Vitals Vault can help you start with labs, then share results with a clinician and discuss options.
- The most dangerous tadalafil interactions are with nitrates and riociguat, which can cause severe low blood pressure.
- Some alpha blockers, blood pressure medicines, and alcohol can add to blood pressure lowering effects.
- Strong CYP3A4 inhibitors and inducers can raise or lower tadalafil levels, changing side effects or effectiveness.
- Tell your clinician about all prescriptions, OTC meds, and supplements before using tadalafil.
What interacts with tadalafil most?
Nitrates
This includes nitroglycerin and other nitrate medicines used for angina (chest pain). Combining nitrates with tadalafil can cause a large blood pressure drop. If you need emergency care for chest pain, tell the care team you have taken tadalafil.
Riociguat
Riociguat is a soluble guanylate cyclase stimulator. Using it with tadalafil can cause significant low blood pressure. This combination is listed as a contraindication in prescribing information.
Some blood pressure lowering agents
Tadalafil can lower blood pressure on its own, so combining it with other blood pressure lowering medicines can increase lightheadedness. The risk varies by the specific medication and your baseline blood pressure.
Key tadalafil interactions explained
Nitrates for chest pain
Nitrates increase nitric oxide signaling, and tadalafil also increases this pathway by blocking PDE5. Together, they can cause profound vasodilation (blood vessel widening) and severe hypotension (low blood pressure). This is why nitrates are contraindicated with tadalafil.
Riociguat for pulmonary hypertension
Riociguat and tadalafil both increase cyclic GMP, which can amplify blood pressure lowering. Prescribing information warns against using them together due to symptomatic hypotension risk.
Alpha blockers for prostate or BP
Alpha blockers can lower blood pressure, and tadalafil can add to that effect. This can show up as dizziness, lightheadedness, or fainting, especially when standing up quickly. Your clinician may adjust timing or choose alternatives depending on which alpha blocker you use.
Other antihypertensives
Many blood pressure medicines can be used with tadalafil, but the combination may increase the chance of low blood pressure symptoms in some people. If you feel faint, have new chest symptoms, or fall, contact a clinician promptly.
CYP3A4 inhibitors
Some medicines slow tadalafil breakdown by inhibiting CYP3A4, which can raise tadalafil levels and side effects. Examples include certain azole antifungals and some HIV medicines. Prescribing information recommends dose adjustments or avoidance with strong inhibitors.
CYP3A4 inducers
Some medicines speed up tadalafil breakdown by inducing CYP3A4, which can lower tadalafil levels and reduce effect. Examples include rifampin. Your clinician may consider different options if you need an inducer long term.
| Interaction category | Examples | Why it matters | What to discuss with a clinician |
|---|---|---|---|
| Contraindicated | Nitrates; riociguat | Can cause dangerous low blood pressure | Whether tadalafil is appropriate and what alternatives fit your condition |
| Use caution | Alpha blockers; other antihypertensives; alcohol | May increase dizziness or fainting risk | How to reduce risk based on your BP, other meds, and symptoms |
| Changes tadalafil levels | Strong CYP3A4 inhibitors or inducers | May increase side effects or reduce effectiveness | Whether dosing needs adjustment or a different ED option is safer |
When to talk to a clinician or seek urgent care
Chest pain or heart symptoms
Get urgent care for chest pain, pressure, shortness of breath, or sweating that could be cardiac. Tell the care team you have taken tadalafil so they can choose safe medicines, especially if nitrates are being considered.
Fainting or severe dizziness
If you pass out, nearly pass out, or cannot stay upright, seek urgent evaluation. This can be a sign of dangerously low blood pressure from an interaction or another medical problem that needs prompt care.
Vision or hearing changes
Sudden vision loss or sudden decrease or loss of hearing needs urgent medical attention. These events are rare but are listed as serious warnings for PDE5 inhibitors, including tadalafil.
Erection lasting too long
An erection lasting more than 4 hours (priapism) is a medical emergency because it can damage tissue. Get urgent care rather than waiting for it to resolve.
Medication list changes
Contact your clinician or pharmacist before starting or stopping prescriptions, over the counter medicines, or supplements that may affect blood pressure or CYP3A4. This is especially important if you are prescribed nitrates, riociguat, or an alpha blocker.
Pro tips to reduce interaction risk
Carry an updated med list
Include heart meds, inhalers, eye drops, and supplements.
Name chest pain medicines
Ask if any of your meds are nitrates or nitrate like.
Ask about CYP3A4
Some antifungals, antibiotics, and HIV meds can change tadalafil levels.
Watch for low BP symptoms
Lightheadedness, fainting, and falls can signal an interaction.
Use one prescriber when possible
It helps catch duplicate therapies and risky combinations.
Frequently Asked Questions
What are the most dangerous tadalafil interactions?
The highest risk tadalafil interactions are with nitrates (used for chest pain) and with riociguat (used for pulmonary hypertension). These combinations can cause dangerously low blood pressure, fainting, and medical emergencies. Confirm with your pharmacist whether any of your medicines are nitrates.
Can you take tadalafil with blood pressure medication?
Sometimes, yes, but tadalafil can lower blood pressure and may add to the effect of antihypertensives. This can cause dizziness or fainting in some people. A clinician can review your medication list and blood pressure to reduce risk.
Do antibiotics or antifungals interact with tadalafil?
Some do. Certain medicines can inhibit or induce CYP3A4, an enzyme that affects tadalafil levels, which can change side effects or effectiveness. Ask your clinician or pharmacist to check for CYP3A4 interactions before starting a new anti-infective.
Is it safe to drink alcohol with tadalafil?
Alcohol can lower blood pressure and can worsen dizziness or fainting when combined with tadalafil. Your risk depends on how much you drink and what other medicines you take. If you notice lightheadedness or falls, contact a clinician promptly.
What should I tell emergency staff if I took tadalafil?
Tell them you took tadalafil and when you last took it, especially if you have chest pain. This helps them avoid nitrates and choose safer alternatives when appropriate. If you have severe symptoms, seek urgent care rather than trying to manage it at home.