Biperiden, anticholinergic drug

Certain anticholinergic drugs such as benz-tropine, biperiden, and trihexyphenidyl are approved for use in treating Parkinson disease (see Chapter 10, Table 10-2 for a more complete list). These drugs... 

Abnormal involuntary movements occurred in 4 cases shortly after starting treatment with 12 mg daily (49 ). When combined with levodopa therapy with and without a decarboxylase inhibitor abnormal involuntary movements appeared in 5 cases. On withdrawal of biperiden, involuntary movements were reduced but parkinsonism symptoms returned. Resumption of the anticholinergic drug resulted in a return of involuntary movements (50 ). 

Acute dystonias occur immediately after neuroleptization and are manifested by motor impairments, particularly in the head, neck, and shoulder region. After several days to months, a parkinsonian syndrome (pseudoparkinsonism) or akathisia (motor restlessness) may develop. All these disturbances can be treated by administration of antiparkin-son drugs of the anticholinergic type, such as biperiden (i.e., in acute dystonia). As a rule, these disturbances disappear after withdrawal of neuroleptic medication. Tardive dyskinesia may become evident after chronic neuroleptization for several years, particularly when the drug is discontinued. It is due to hypersensitivity of the dopamine receptor system and can be exacerbated by administration of anticholinergics. 

Trihexyphenidyl and biperiden have strong central and peripheral anticholinergic activity and both idiopathic as well as drug-induced Parkinsonism can be an indication for their use. Especially the tremor of Parkinsonism is favorably influenced. Large doses of trihexyphenidyl are said to have a mood modifying effect. The existence of a parenteral dosage forms of biperiden extends the applications of this agent. Both have a duration of action of 6-12 hours. 

Geriatric Considerations- Summary Biperiden is a weak anticholinergic agent which still may present a risk to older adults and can cause cognitive impairment, delirium, dry mouth, blurred vision, and increased risk of falls. The use of this drug and related compounds should be limited and when used, patients should be closely monitored. 

Some of the drugs responsible are amitriptyline, amoxapine, atropine, benztropine, biperiden, didinium, cyclobenzaprine, desipramine, doxepin, hyoscyamine, imipramine, lorazepam, maprotiline, nortriptyline, protriptyline, propantheline, scopolamine, trimipramine. Some herbals that can elicit the anticholinergic syndrome are black henbane, deadly nightshade, Devil s apple, Jimson weed, Loco seeds or weeds, Matrimony vine, night blooming jessamine, stinkweed. 

Benztropine mesylate (cogentin, others), biperiden (akineton), procycUdine (kemadrin), and trihexyphenidyl hydrochloride (artane, others) are tertiary-amine muscarinic receptor antagonists (together with the ethanolamine antihistamine diphenhydramine [benadryl, others]) that gain access to the CNS and can therefore be used when anticholinergics are indicated to treat parkinsonism and the extrapyramidal side effects of antipsychotic drugs (see Chapter 20). 

---