In general, Cialis (tadalafil) is OK to use with most blood pressure medication and there are no serious interactions. The one exception may be with a specific class of blood pressure medication known as 'alpha blockers'.


A well known side effect of erectile dysfunction drugs such as Cialis is possible hypotension, or too low blood pressure. While fairly uncommon when taking Cialis alone (~2% incidence in clinical trials), the chance is augmented when used in combination with other medications that can drop blood pressure.


In addition to alpha blockers, we commonly hear that Cialis should not be taken with nitrates, as the combination could result in a significant and potentially serious drop in blood pressure. There have been reports of severe side effects such as hypotension, dizziness and heart attack in those using Cialis while taking a nitrate or are on nitrate therapy. Common 'nitrate' medications include:

  • Isosorbide Mononitrate
  • Isosorbide Dinitrate
  • Nitroglycerine


Aside from nitrates, most other blood pressure medications classes do not represent a significant risk. Beta blockers, ACE-Inhibitors, ARBs and diuretic medications are blood pressure medications that are generally considered to be OK to use while on Cialis as long as your blood pressure is well controlled and isn't dropping too low from medication use.


As mentioned above, there is a class of blood pressure medications that is considered risky to use, the 'alpha blocker' class of medications. The risk of hypotension with the use of Cialis and alpha blockers is far greater when compared to other blood pressure medications.


Per the prescribing information for Cialis, patients should be stabilized on alpha blockers medication before starting on Cialis and Cialis should be started at the lowest possible dose (2.5 mg to 5 mg). If you are already on Cialis and your doctor wants you to begin therapy on alpha blockers, they are recommended to be started at the lowest possible dose and tapered to appropriate effect. Common alpha blocker medications include:

  • Doxazosin
  • Terazosin
  • Phenoxybenzamine
  • Prazosin


So, to reiterate, most blood pressure medications are considered to be safe to use in combination with Cialis. The main medication classes of concern are alpha blockers and nitrates. Nitrates are contraindicated in those taking Cialis while alpha blockers need to be used with caution. If you experience symptoms of low pressure while taking Cialis and blood pressure medication, it is important to let your doctor know as your therapy may need to be adjusted.