The most prominent side effect is sedation. A typical dose creates driving impairment equivalent to a blood-alcohol level of 0.10, which is higher than the 0.08 limit of most drunk-driving laws.<unk>  is a potent anticholinergic agent and potential deliriant in higher doses. This activity is responsible for the side effects of dry mouth and throat, increased heart rate, pupil dilation, urinary retention, constipation, and, at high doses, hallucinations or delirium. Other side effects include motor impairment (ataxia), flushed skin, blurred vision at nearpoint owing to lack of accommodation (cycloplegia), abnormal sensitivity to bright light (photophobia), sedation, difficulty concentrating, short-term memory loss, visual disturbances, irregular breathing, dizziness, irritability, itchy skin, confusion, increased body temperature (in general, in the hands and/or feet), temporary erectile dysfunction, and excitability, and although it can be used to treat nausea, higher doses may cause vomiting.<unk>  in overdose may occasionally result in QT prolongation. Some individuals experience an allergic reaction to<unk>  in the form of hives. Conditions such as restlessness or akathisia can worsen from increased levels of<unk> , especially with recreational dosages. Normal doses of<unk> , like other first generation antihistamines, can also make symptoms of restless legs syndrome worse. As<unk>  is extensively metabolized by the liver, caution should be exercised when giving the drug to individuals with hepatic impairment. Anticholinergic use later in life is associated with an increased risk for cognitive decline and dementia among older people.
Diphenhydramine
Olopatadine
Ephedrine
Pseudoephedrine
Meclizine
Lofepramine
Dezocine
Molsidomine