Haloperidol trihexyphenidyl

Extracted clorazepate, nordiazepam, oxazepam, temazepam, triazolam Simultaneous bromazepam, flunitrazepam, nitrazepam, sulpride Noninterfering haloperidol, trihexyphenidyl... 

A 30-year-old man with bipolar disorder who had previously taken haloperidol and lithium was also given trihexyphenidyl (benzhexol) because of rigidity, tremor, and akathisia, but persistent symptoms led to his being given olanzapine in place of haloperidol 6 days later he developed priapism (242). 

Concomitant nse with amantadine may amplify trihexyphenidyl s anticholinergic adverse effects, causing confusion and haUncinations. Concomitant use with haloperidol or phenothiazines may decrease the antipsychotic effectiveness of these drugs, possibly from direct CNS antagonism concomitant phenothiazine nse also increases the risk of anticholinergic adverse effects. 

Extracted acetophenazine, benztropine, butaperazine, carphenazine, chlorpromazine, flu-phenazine, haloperidol, imipramine, mesoridazine, nortriptyline, orphenadrine, pipera-cetazine, promazine, promethazine, thioridazine, thiothixene, trifluoperazine, trifluprom-azine, trihexyphenidyl, trimeprazine... 

Simultaneous amitriptyline, amoxapine, benztropine, brompheniramine, chlorpheniramine, chlorpromazine, clomipramine, cyproheptadine, desipramine, dothiepin, doxepin, fluoxetine, haloperidol, imipramine, loxapine, maprotiline, meperidine, mesoridazine, methadone, metoclopramide, mianserin, moclobemide, nomifensine, nordoxepin, norfluox-etine, norpropoxyphene, northiaden, pentobarbital, pheniramine, promethazine, propoxyphene, propranolol, protriptyline, quinidine, quinine, sulforidazine, thioridazine, thiothixene, tranylcypromine, trazodone, trihexyphenidyl, trimipramine, triprolidine... 

Three patients treated with various antipsychotics (fluphenazine, ha-loperidol, trifluoperazine, chlorpromazine) developed Stevens-Johnson syndrome within 8 to 14 days of starting to take carbamazepine. All 3 had erythema multiforme skin lesions and at least two mucous membranes were affected. After treatment, all 3 were restarted on all their previous drugs, except carbamazepine, without problems. Another case of Stevens-Johnson syndrome has been reported in a patient taking carbamazepine, lithium carbonate, haloperidol and trihexyphenidyl. The reasons are not understood. Stevens-Johnson syndrome with carbamazepine alone is rare, and the risk appears to be mostly confined to the first 8 weeks of treatment. It may be more common in patients being treated for conditions other than epilepsy. It is not possible to say whether the concurrent use of antipsychotics increases the risk of its development, but until more is known it would be prudent to monitor the outcome, particularly during the first 2 weeks of combined use. 

Haloperidol. A study in 9 schizophrenics taking haloperidol (average dose 30 mg daily) found a 55% reduction in plasma haloperidol levels (a mean fall from 45.5 to 21.2 nanograms/mL) when they were given carbamazepine for 5 weeks (precise dose not stated). They also took trihexyphenidyl 10 mg daily and oxazepam 30 mg at night as necessary. Carbamazepine serum levels and the control of the disease remained unchanged. 

Other studies confirm that trihexyphenidyl and orphenadiine reduce the plasma levels and effects of chlorpromazine. In contrast to these reports, another found that trihexyphenidyl increased chlorpromazine levels by 41% in 20 young schizophrenics, but no clinical change was seen. The levels dropped again over the first 4 weeks of treatment. Some of the beneficial actions of haloperidol on social avoidance behaviour ate lost during concurrent treatment with benzatropine, but cognitive integrative function is unaffected. 

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