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Akathisia: Is Restlessness a Primary Condition Or an Adverse Drug Effect?

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Akathisia: Is Restlessness a Primary Condition Or an Adverse Drug Effect? Akathisia: Is restlessness a primary condition or an adverse drug effect? Keep a discerning eye out for this adverse effect of antipsychotics and other drugs kathisia—from the Greek for “inability to sit”—is a neuropsychiatric syndrome characterized by subjective Aand objective psychomotor restlessness. Patients typi- cally experience feelings of unease, inner restlessness mainly involving the legs, and a compulsion to move. Most engage in repetitive movement. They might swing or cross and uncross their legs, shift from one foot to the other, continuously pace, or persistently fidget. In clinical settings, akathisia usually is a side effect of medi- cation. Antipsychotics, serotonin reuptake inhibitors, and buspirone are common triggers, but akathisia also has been associated with some antiemetics, preoperative sedatives, calcium channel blockers, and antivertigo agents. It also can PHOTO ILLUSTRATION BY PAT PHOTOFOPMA ILLUSTRATION BY PAT be caused by withdrawal from an antipsychotic or related to Fernando Espi Forcen, MD a substance use disorder, especially cocaine. Akathisia can be Fellow, Psychosomatic Medicine acute or chronic, occurring in a tardive form with symptoms Department of Psychiatry and Behavioral Sciences 1-3 Memorial Sloan Kettering Cancer Center that last >6 months. New York, New York Much isn’t known about drug-induced akathisia Our understanding of the pathophysiology of akathisia is incomplete. Some have suggested that it results from an imbal- ance between the dopaminergic/cholinergic and dopaminer- gic/serotonergic systems4; others, that the cause is a mismatch between the core and the shell of the nucleus accumbens, due in part to overstimulation of the locus ceruleus.5 More recently, researchers established a positive asso- ciation between higher scores on the Liverpool University Disclosure Current Psychiatry Dr. Forcen reports no financial relationships with any company whose products are mentioned in 14 January 2015 this article or with manufacturers of competing products. Neuroleptic Side Effects Rating Scale and Box 1 D2/D3 receptor occupancy in the ventral striatum (nucleus accumbens and olfactory Think twice before increasing tubercle).6 The D2/D3 receptor occupancy the dosage model might explain withdrawal symptoms atients who develop symptoms of associated with cocaine,7 as well as rela- Pakathisia sometimes stop taking their tive worsening of symptoms after tapering medication; this often results in psychiatric 12 or discontinuing stimulants in attention- relapse. In addition, symptoms of akathisia often mimic psychiatric symptoms and deficit/hyperactivity disorder (ADHD). can be mistaken for worsening anxiety or psychosis; in such cases, a practitioner might increase the dosage of the agent that is causing akathisia, potentially leading to Elements of a clinical evaluation further deterioration of the clinical picture. When akathisia is suspected, evaluation Psychiatric patients admitted to the hospital by a clinician familiar with its phenom- also are vulnerable. Last, patients who do not adhere to their enology is crucial. A validated tool, such as outpatient drug regimen can develop akathisia the Barnes Akathisia Rating Scale (at out when they begin receiving all their scheduled cometracker.org/library/BAS.pdf) can aid medications—and could be subject to chemical Clinical Point 8 or physical restraint if agitation results. in the detection and assessment of severity. The inner restlessness In evaluating patients, keep in mind that the inner restlessness that characterizes that characterizes akathisia can affect the trunk, hands, and akathisia can affect arms, as well as the legs, and can cause dys- nician to increase the dosage of the drug that the trunk, hands, phoria and anxiety. Akathisia has been linked is causing akathisia (Box 112). and arms, as well as to an increased likelihood of developing sui- the legs, and can cause cidal ideation and behavior.9 Less common subjective symptoms Managing drug-induced dysphoria and anxiety include rage, fear, nausea, and worsening akathisia of psychotic symptoms. Because of its asso- Akathisia usually resolves when the drug ciation with aggression and agitation, drug- causing it is discontinued; decreasing the induced akathisia has been cited—with dosage might alleviate the symptoms. little success—as the basis for an insanity Whenever akathisia is detected, careful defense by people who have committed a revision of the current drug regimen— violent act.10 substituting an antipsychotic with a lower prevalence of akathisia, for example— should be considered (Box 2,13-16 page 16). Or is akathisia another Treatment of drug-induced akathisia, which psychiatric disorder? should be tailored to the patient’s psycho- Akathisia might go undetected for several pathology and comorbidities, is needed as reasons. One key factor: Its symptoms resem- well (Table,17-25 page 17). ble and often overlap with those of other psy- chiatric disorders, such as mania, psychosis, Beta blockers, particularly propranolol, agitated depression, and ADHD. In addition, are considered first-line therapy for drug- akathisia often occurs concurrently with, and induced akathisia, with a dosage of 20 to 40 mg is masked by, akinesia, a common extrapy- twice daily used to relieve symptoms26 ramidal side effect of many antipsychotics. The effect can be explained by adrenergic Such patients might have the inner feeling terminals in the locus ceruleus and ending in Discuss this article at of restlessness and urge to move but do not the nucleus accumbens and prefrontal cor- www.facebook.com/ CurrentPsychiatry exhibit characteristic limb movements. In tex stimulate β adrenoreceptors.5,27 Although some cases, cognitive or intellectual limita- multiple small studies and case reports26,28-32 tions prevent patients from communicating support the use of beta blockers to treat drug- the inner turmoil they feel.11 induced akathisia, the quality of evidence of Medication nonadherence further compli- their efficacy is controversial.12,21,27 Consider Current Psychiatry cates the picture, sometimes prompting a cli- the risk of hypotension and bradycardia and Vol. 14, No. 1 15 Box 2 with antipsychotic-induced akathisia.37 The recommended dose is 8 to 16 mg/d. Selecting an antipsychotic A study using the selective inverse ago- with akathisia in mind nist pimavanserin (not FDA-approved) igh-potency, first-generation decreased akathisia in healthy volunteers Hantipsychotics have a higher prevalence taking haloperidol.14,24,33 of akathisia, compared with low to Zolmitriptan, a 5-HT1D agonist, also can Akathisia intermediate potency first- and second- be used38; one study found that 7.5 mg/d of generation antipsychotics (SGAs). SGAs 39 differ in terms of their propensity for akathisia zolmitriptan is as effective as propranolol. as well, with higher rates reported for A 2010 study showed a statistically signifi- aripiprazole and lurasidone compared with cant improvement in 8 patients taking trazo- iloperidone, quetiapine, and clozapine; the latter are no more likely than placebo to cause done, compared with 5 patients on placebo, akathisia.13 It’s necessary to carefully consider all of whom met criteria for at least mild the risk-benefit ratio before prescribing an akathisia. Trazodone’s antiakathitic effect is SGA that has a greater propensity to cause 25 akathisia.14-16 attributed to its 5-HT2A antagonism. Clinical Point Anticholinergics. Traditionally, benztropine, Data are insufficient biperiden, diphenhydramine, and trihexy- be aware of contraindications for patients phenidyl have been used for prevention and to support use of with asthma or diabetes. treatment of extrapyramidal side effects. A anticholinergics for Cochrane review concluded, however, that akathisia, a Cochrane Low-dose mirtazapine (15 mg/d) was data are insufficient to support use of anticho- Review concluded found to be as effective as propranolol, linergics for akathisia.40 Although multiple 80 mg/d, in a placebo-controlled study, and case reports have shown anticholinergics to to be more effective than a beta blocker in be effective in treating drug-induced akathi- treating akathisia induced by a first-gener- sia,12,17,33 their association with cognitive side ation antipsychotic. The authors concluded effects suggests a need for caution.18 that both propranolol and mirtazapine should be first-line therapy.23 Others have Benzodiazepines. Through their sedative suggested that these results be interpreted and anxiolytic properties, benzodiazepines with caution because mirtazapine (at a are thought to partially alleviate akathisia higher dosage) has been linked to akathi- symptoms. Two small trials found clonaz- sia.33 Mirtazapine blocks α-adrenergic epam helpful for akathisia symptoms2,20; and receptors, resulting in antagonism of 5-HT2 1 case report revealed that a patient with and 5-HT3 receptors and consequent akathisia improved after coadministration enhancement of 5-HT1A serotonergic trans- of clonazepam and baclofen.41 mission.34 In one study, it was shown to reduce binding of the D2/D3 receptor ago- Anticonvulsants. Valproic acid has not nist quinpirole.35 been found to be useful in antipsychotic- induced tardive akathisia.42 However, a case Serotonin antagonists and agonists. report described a patient with schizophrenia Blockade of 5-HT2 receptors can attenuate whose akathisia symptoms improved after D2 blockade and mitigate akathisia symp- the dosage of gabapentin was increased.43 toms. Mianserin, 15 mg/d, can be helpful,
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