Antihistamines confusion caused

In addition to sedation, many oral antihistamines can cause hypotension, dizziness, blurred vision, and confusion.28... 

Antihistaminics are rather notorious from the standpoint of the diverse reactions which they elicit from individuals. Benadryl, according to a typical report,42 caused side reactions in 133 out of 217 patients to whom it was administered. Drowsiness was reported for 93 patients, dry mouth for 44, parasthesias of the hands for 32, headache for 21, dizziness for 15, nervousness for 8, tinnitus for 8, vomitingfor 4, confusion for 3, narcolepsy for 2, weakness for 2, and diarrhea for. Even if the complete accuracy of such reports is ques-... 

With long-term use, the most problematic side effect is weight gain. However, many antihistamines including diphenhydramine also possess potent anticholinergic effects. This can cause dry mouth, blurred vision, constipation, confusion, and urinary retention. Because anticholinergic effects are especially problematic for the elderly, we advise against the routine use of antihistamines to treat elderly patients with insomnia. 

Quazepam (Doral) [C IV] [Sedative/Hypnotic/ Benzodiazepine] Uses Insomnia Action Benzodiazepine Dose 7.5-15 mg PO hs PRN i in elderly hqjatic failure Caution [X, /-] NA glaucoma Contra PRG, sleep apnea Disp Tabs SE Sedation, hangovCT, somnolence, resp depression Interactions T Effects W/ azole antifungals, cimetidine, digoxin, disulfiram, INH, levodopa, macrolides, neuroleptics, phenytoin, quinolones, SSRIs, verapamil, grapefruit juice, EtOH effects W/carbamazepine, rifampin, rifabutin, tobacco EMS Use caution w/ other benzodiazepines, antihistamines, opioids and verapamil, can T CNS depression concurrent EtOH and grapefruit juice use T CNS depression OD May cause profound CNS depression, confusion, bradycardia, hypotension, and altered reflexes flumazenil can be used as antidote activated charcoal may be effective... 

Antimuscarinic syndromes consist of tachycardia, dilated pupils, dry, flushed skin, urinary retention, decreased bowel sounds, mild elevation of body temperature, confusion, cardiac arrhythmias and seizures. They are commonly caused by antipsych-otics, tricyclic antidepressants, antihistamines, anti-spasmodics and many plants (see p. 160). 

Some antihistamines, for example tripellenamine (often used in combination with pentazocine), have a particular abuse potential and are used by drug addicts. Psychiatric disturbances, dysphoria, depression, confusion, and hallucinations can occur while under the influence of an antihistamine or during drug withdrawal. Chronic parenteral abuse can cause skin lesions, muscular fibrosis, and vasculitis. 

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