Antihistamines

Some antihistamines with sedating properties, such as diphenhydramine, hydroxyzine and doxylamine, are effective in treating mild types of insomnia. However, these drugs are usually ineffective for all but the milder forms of situational insomnia. Furthermore, they have numerous undesirable side effects (such as anticholinergic effects) that make them less useful than the benzodiazepines. Some sedative antihistamines are marketed in numerous over-the-counter products.