ReviewTherapeutic potential of histaminergic compounds in the treatment of addiction and drug-related cognitive disorders

Addiction is a behavioral disorder characterized by the compulsive seeking and taking of drugs despite serious negative consequences. In particular, the chronic use of drugs impairs memory and cognitive functions, which aggravates the loss of control over drug use and complicates treatment outcome. Therefore, cognitive enhancers targeting acetylcholine have been proposed to treat addiction. Interestingly, histamine H3 receptor (H3R) antagonists/inverse agonists stimulate acetylcholine transmission in different brain areas, facilitate memory in animal models and can reverse learning deficits induced by drugs such as scopolamine, dizocilpine and alcohol. Moreover, several studies found that compounds capable of activating the histaminergic system generally decrease the reinforcing effects of drugs, namely alcohol and opioids, in preclinical models of addiction. Finally, several H3R antagonists/inverse agonists increase histamine in the brain and have proven to be safe in humans. However, no studies have yet investigated the therapeutic potential of cognitive enhancing H3R antagonists/inverse agonists in the treatment of addiction in humans. The present review first describes the impact of addictive drugs on learning processes and cognitive functions that play an important role for addicts to remain abstinent. Second, our work briefly summarizes the relevant literature describing the function of histamine in learning, memory and drug addiction. Finally, the potential therapeutic use of histaminergic agents in the treatment of addiction is discussed. Our review suggests that histaminergic compounds like H3R antagonists/inverse agonists may improve the treatment outcome of addiction by reversing drug-induced cognitive deficits and/or diminishing the reinforcing properties of addictive drugs, especially opioids and alcohol.

► Addictive drugs cause cognitive deficits that compromise treatment outcome. ► Histamine H3R antagonists/inverse agonists have cognition enhancing properties. ► H3R blockade can attenuate the rewarding effects of opioids and alcohol. ► Several H3R antagonists/inverse agonists have proven to be safe in humans. ► H3R inverse agonists may be useful for the treatment of drug addiction.