A person with violent behavior and agitation was diagnosed to have Schizophrenia and was receiving haloperidol. Following this he developed rigidity and inability to move his eyes. Which of the following drugs should be added to his treatment intravenously for this condition?
Ans. c. Promethazine (Ref: Harrison 19/e p2624, 18/e p3544. Katzung 12/e p495)Rigidity and inability to move eyes after haloperidol use in a patient of Schizophrenia is highly suggestive of acute muscular dystonia. Treatment with IM anticholinergic (benztropine) or IV/IM antihistaminic (diphenhydramine hydrochloride almost always relieves the symptoms. Promethazine, 25-50 mg IV or IM, has been used less frequently but readily available.Acute Muscular Dystonia:Bizarre muscle spasms, mostly involving linguo-facial muscles-grimacing, torticollis, locked jawQOccurs within few hours of single dose or at the most in the first week of therapyQMore common in children below 10 years and in girls, particularly after parenteral administrationQTreatment: Central anticholinergicQ, promethazineQ or hydroxyzineNeuroleptic Induced Acute DystoniaAbout 10% of all patients experience dystonia as an adverse effect of dopamine receptor antagonist, usually in the first few hours or days of treatmentQ (early onset during the course of treatment with neuroleptics).Most common in young men (< 40 years old)Most common with high doses of high potency dopamine receptor antagonistQ especially via IM route (haloperidol is high potency drug and 20 mg/day is high dose), shortly after starting the drug or increasing its doseQ.It results from dopaminergic hyperactivity in the basal ganglia, that occurs when the CNS levels of dopamine receptor antagonist drug begin to fall between doses.Clinical Features:Dystonic movements result from a slow, sustained muscular contraction or spasm that can result in an involuntary movement. It can involve the:* Face (grimacing)Q* Neck (spasmodic torticollisQ or retrooollis)* Jaw (forced opening resulting in dislocation of jaw or trismusQ)* Tongue (protrusions, twisting)Q* Eye (oculogyric crisisQ characterized by eyes' upward lateral movement)* Dystonic posture of limb and trunkQ* Spinal muscles (opisthotonos)Q* Blepharospasm, glossopharyngeal and laryngopharyngeal dystonia, which can result in dysarthria, dysphagia, and even trouble breathing, which can cause cyanosisUnlike other types of dystonia, an oculogyric crisis may occur late in treatment.Children are particularly likely to exhibit opisthotonos, scoliosis, lordosis, and writhing movements.Treatment:Treatment with IM anticholinergic (benztropine) or IV/IM antihistaminic (diphenhydramine hydrochloride)Q almost always relieves the symptoms.Promethazine, 25-50 mg IV or IM has been used less frequently but readily availableExtrapyramidal Disturbances of anti-Psychotic drugsThese are the major dose limiting side effectsQMore prominent with high potency drugs like fiuphenazine, haloperidol, pimozide etcQ.Least with thioridazine, clozapine, olanzapine, and low doses of resperidoneQ.These are of following types:Parkinsonism:With typical manifestations-rigidity, tremor, hypokinesia, mask like facies, shuffling gaitQAppears between 1-4 weeks of therapyQTreatment: Central anticholinergic drugsQRabbit syndromeA rare form of extrapyramidal side effect is perioral tremors "rabbit syndrome"Occurs years after of therapyTreatment: Central anticholinergic drugsQAcute muscular dystonia:Bizarre muscle spasms, mostly involving linguo-facial muscles-grimacing, torticollis, locked jawQOccurs within few hours of single dose or at the most in the first week of therapyQMore common in children below 10 years and in girls, particularly after parenteral administrationQTreatment: Central anticholinergicQ, promethazineQ or hydroxyzineAkathisia:Restlessness, feeling of discomfort, apparent agitation manifested as compelling desire to move about but without anxietyQBetween 1-8 weeks of therapyQNo specific antidote is availableTreatment: PropranololQMalignant neuroleptic syndrome:Occurs rarely with high doses of potent agentsQMarked rigidity, immobility, tremor, fever, semi-consciousness, fluctuating BP and heart rate, myoglobin may be present in blood-lasts 5-10 days after drug withdrawal and may be fatalQ.Treatment: Stop neuroleptic. BromocriptineQTardive dyskinesia:Occurs late in therapy (Chronic therapy), sometimes even after withdrawal of neurolepticQManifests as purposeless involuntary facial and limb movements like constant chewing, pouting, puffing of cheeks, lip licking, choreoathetoid movementsQMore common in elderly womenQProbably a manifestation of progressive neuronal degeneration along with supersensitivity to DAAccentuated by anticholinergics and temporarily suppressed by high doses of neurolepticsQ
Diazepam
Resperidone
Promethazine
Haloperidol
Schizophreniform Disorder