Q:  ACE inhibitors have documentation to cause hallucinations via central effect, particularly in elderly patients. Which drug may reverse this effect?



Answer:  Naloxone

Aging process is the biggest risk factor for ACE inhibitor–induced visual hallucinations.  Also, This may be a diagnosis of exclusion or may require challenge with drug again to prove the diagnosis! ACE inhibitors that cross the blood brain barrier include captopril, fosinopril, lisinopril, perindopril, ramipril, and trandolapril. Benazepril, enalapril, moexipril, and quinapril do not cross the blood-brain barrier. Ironically, captopril has been researched for slowing of Alzheimer's disease but also said that the development of visual hallucinations in elderly patients may suggest underlying Alzheimer's disease!

There are case reports of hallucinations from angiotensin receptor blocker(ARBs) too. 



References:

1. Gillman M, Sandyk R. Reversal of captopril-induced psychosis with naloxone. Am J Psychiatry. 1985;142:270.

2. Sink K, Leng X, Williamson J, et al. Angiotensin-converting enzyme inhibitors and cognitive decline in older adults with hypertension: results from the Cardiovascular Health Study. Arch Intern Med. 2009;169:1195–1202. 

3. Gorelick P, Nyenhuis D, On behalf of the American Society of Hypertension Writing Group. ASH Position Paper: blood pressure and treatment of persons with hypertension as it relates to cognitive outcomes including executive function. J Am Soc Hypertens. 2012;6:309–315.