Can you take Viagra with medication for high blood pressure? Usually yes: most blood-pressure tablets add only a small extra fall in blood pressure, alpha-blockers need a careful start, and nitrates are never allowed. In the Australian label's safety data, men taking blood-pressure medicines had the same side effects as men who were not (Viagra PI (Australia)). The doctor who prescribes Viagra needs your full list of medicines, and blood pressure that is unusually high or low, or not effectively treated, rules Viagra out (Viagra CMI).
Why does Viagra lower blood pressure at all?
Because sildenafil widens blood vessels. After a 100 mg dose, blood pressure lying down fell on average by 8.4 mmHg systolic and 5.5 mmHg diastolic, a mild and passing drop that the Australian label calls "of little or no consequence in most patients" (Viagra PI (Australia)). Blood-pressure medicines lower it too, so the two effects add, which is why healthdirect lists blood pressure medicines among sildenafil's interactions (healthdirect — Sildenafil). The Australian label rules sildenafil out below 90/50 mmHg and above 170/110 mmHg, where its safety was not studied (Viagra PI (Australia)).
What do the labels say about each class of blood-pressure medicine?
Most classes made no measurable difference. healthdirect groups the medicines as ACE inhibitors and sartans (ARBs), calcium channel blockers, diuretics (fluid tablets), beta-blockers and alpha-blockers; the most common are ACE inhibitors, calcium channel blockers and diuretics (healthdirect — Blood pressure medicines). The sildenafil label pooled every one of these classes and found no difference in side effects between sildenafil and placebo (EMA — Viagra). Class by class:
| Class (names often end in) | What the sildenafil label found | Our page |
|---|---|---|
| ACE inhibitors (-pril) and sartans (-sartan) | ACE inhibitors did not change sildenafil levels. With sacubitril/valsartan, sildenafil lowered blood pressure significantly more, so the European label asks for caution. | ramipril, lisinopril |
| Calcium channel blockers (-pine) | With amlodipine, blood pressure fell a further 8/7 mmHg, about what sildenafil does on its own. | amlodipine |
| Diuretics (-zide, indapamide) | Did not change sildenafil levels. | this page |
| Beta-blockers (-lol) | Did not change sildenafil levels. | beta-blockers, carvedilol |
| Alpha-blockers (doxazosin; for the prostate, alfuzosin, tamsulosin) | Caution: low blood pressure with symptoms in a few men. Be stable on the alpha-blocker first; start sildenafil low. | alfuzosin |
| Vasodilators (minoxidil tablets) | Pooled with the rest: no extra side effects. | minoxidil |
| Nitrates (for angina, not blood pressure) | Never: "Nitrates and VIAGRA must not be used concomitantly." | nitroglycerin |
Sources: Viagra PI (Australia) (levels, amlodipine, alpha-blockers, nitrates); EMA — Viagra (pooled side effects, sacubitril/valsartan); minoxidil tablets work by relaxing the blood vessels (Loniten CMI).
Why do alpha-blockers need more care?
Because they can drop blood pressure on standing. Doxazosin, an alpha-blocker used for blood pressure or the prostate, was tested with sildenafil in men with an enlarged prostate who were already stable on it: standing blood pressure fell a further 4 to 11 mmHg systolic, and a few men reported dizziness and light-headedness, though none fainted (Viagra PI (Australia)). The European label says this is most likely within 4 hours of the dose. Both labels say to be stable on the alpha-blocker before starting sildenafil and to consider a lower first dose; the European label names 25 mg (EMA — Viagra).
What about Cialis?
Similar, with one class to watch. Adding tadalafil to enalapril, metoprolol, bendrofluazide, amlodipine or tamsulosin gave no significant extra fall on average, though some individuals had larger drops. In 17 people taking sartans, systolic pressure fell by 30 mmHg or more in 53% after tadalafil 20 mg, against 29% after placebo, with no symptoms. With doxazosin, fainting was among the symptoms reported in studies (Cialis PI (Australia)).
Could the blood-pressure tablets be causing the erection problem?
Sometimes. healthdirect notes that some medicines for blood pressure can affect erections, and that erectile dysfunction can be the first sign of high blood pressure itself (healthdirect — Erectile dysfunction). Two classes have their own pages: can amlodipine cause erection problems? and beta-blockers and erectile dysfunction. Do not stop a blood-pressure medicine on your own; ask the doctor who prescribed it.
What should you watch for after a dose?
Dizziness or light-headedness, especially when you stand up. If Viagra makes you dizzy, do not drive, and fainting is one of the side effects that mean telling your doctor or going to the emergency department (Viagra CMI). Chest pain during or after sex is an emergency: call 000, and never take a nitrate spray or tablet after Viagra (Viagra PI (Australia)).
The short answer
Most blood-pressure tablets can be taken with Viagra: the label found no extra side effects across the classes, and amlodipine added about the fall sildenafil causes alone. Alpha-blockers need a stable dose first and a low start; nitrates are ruled out. Every other combination is in can Viagra be taken with other medicines? and our guide to taking Viagra or Cialis with other medicines.
