 Alcohol acts as an agonist of the GABAA type receptor, leading to memory disruption ("see Effects of alcohol on memory").Benzodiazepines (such as flunitrazepam, midazolam, and temazepam), barbiturates (such as phenobarbital), and other drugs which also act as GABAA agonists, are known to cause blackouts as a result of high dose use.Research indicates that some users of alcohol, particularly those with a history of blackouts, are predisposed to experience blackouts more frequently than others.