kaylasmom recently began taking Lotensin to treat her elevated blood pressure (diabetes-related, so the choice of drug was meant to protect against kidney problems). It has been giving her a headache. The wiki entry for Benazepril indicates that one of the potential side effects is headache. Wiki goes on to say that headache is one of the adverse effects of ACE inhibitors in general.
What wiki does not do is: discuss the mechanism behind the headache side effect. It also does not discuss whether the side effect can be expected to subside as blood concentration approaches therapeutic levels.
I understand that angina patients who take nitroglycerin can experience headache as a result of the vasodilation (although I never learned the mechanism for that either, as I recall). Is something similar going on with ACE inhibitors?
Please understand that I am not asking for medical advice; just some knowledge. We intend to speak with her doctor tomorrow.
ETA: Thanks for any responses. kaylasmom is an insatiably curious woman.
One common mechanism is excess histamine production due to the inhibition of the Angiotensin Converting Enzyme (ACE). This may result in headache, cough, and nasal congestion.
One could try antihistamines like claritin or benadryl to reduce these side-effects.
If the problem is severe enough, one can stop the ACE and use an ARB. One gets the same blood pressure and diabetic/kidney benefit from the ARBs like diovan or losartan, without the histamine buildup. Unfortunately, ARBs are about 15 times as expensive as ACEs.
Qadgop, thanks for your input. I gave kaylasmom some OTC loratadine for a couple of days, and it helped a little. Only a little, though, so on her next visit to the doctor, she asked for an ARB, which he prescribed (and the insurance picked up).
Remarkably, after about a week on Lotensin, the snapshot of her BP decreased significantly, with the diastolic going from of 112 to 88. Here’s hoping she responds similarly to losartan (wikipedia doesn’t list side effects, for some reason. I’m going to go check the Merck website).