Introduction: Respiratory dyskinesia (RD) is characterized by choreoathetoid movements involving laryngopharyngeal and respiratory muscles, with higher occurrence among elderly females. It can often mimic a diverse array of conditions, frequently leading to misdiagnoses such as respiratory, cardiac, or psychogenic in nature (1,2). Initially regarded as a rare complication associated with prolonged neuroleptic treatment, recent studies have highlighted the prevalence of respiratory abnormalities in patients utilizing antipsychotics (3,4). Hayashi et al. study revealed the prevalence of RD to be 17.5% within the tarditive dyskinesia (TD) patients (5). TD is estimated to have an annual incidence of 5% in adults and 25% in the elderly receiving antipsychotics (6). These findings underscore the under-recognized nature of RD as a side effect of chronic neuroleptic administration (4,7,8).

Case presentation: 36-year-old patient with schizoaffective disorder on haloperidol for one year presented with dyspnea and repetitive mouth twitching persisting for six days. Upon physical examination, involuntary movements of the tongue, cheek, and lip were noted. He was hemodynamically stable with a respiratory rate of 36. Chest X-ray and CT angiography showed no acute cardiopulmonary abnormalities. Arterial blood gas analysis demonstrated a pH of 7.63, carbon dioxide level of 13, oxygen level of 126, and bicarbonate level of 13. His white blood cell count was 12.28 x 10³ cells/μL , hemoglobin was 19.5 g/dL and bicarbonate was 15 mmol/L.

Management: VMAT2 inhibitors are the main symptomatic drug therapy for TD, however these agents are not widely available. Therefore, our patient received 1mg of alprazolam followed by 0.5 mg of clonazepam b.i.d and 1mg of benztropine b.i.d. Haloperidol was discontinued, and switched for quetiapine 25mg daily. Subsequently, the symptoms improved rapidly, and he was discharged the following day.

While early diagnosis of RD is essential, there is currently no established objective assessment method. Clinicians should regularly evaluate patients undergoing long-term antipsychotic therapy for evidence of respiratory dyskinesia. Timely identification of RD would prevent unnecessary testing and mismanagement of mistakenly suspected cardiorespiratory causes, thus facilitating prompt intervention and improved patient outcomes. Further research is necessary to establish evidence-based diagnostic criteria and tailor treatment options for respiratory dyskinesia.

References and Resources

1. Kruk J, Sachdev P, Singh S. Neuroleptic-induced respiratory dyskinesia. J Neuropsychiatry Clin Neurosci. 1995 Spring;7(2):223-9. doi: 10.1176/jnp.7.2.223. PMID: 7626967.
2. Bhimanil MM, Khan MM, Khan MF, Waris MS. Respiratory dyskinesia–an under-recognized side-effect of neuroleptic medications. J Pak Med Assoc. 2011 Sep;61(9):930-2. Erratum in: J Pak Med Assoc. 2011 Oct;61(10):1049. Bhimani, Mukesh [corrected to Bhimanil, Mukesh Mohan]; Khan, Murad Moosa [added]; Khan, Muhammad Faheem Ashraf [added]; Waris, Muhammad Shiraz [added]. PMID: 22360044.
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4. Hayashi T, Nishikawa T, Koga I, Uchida Y, Yamawaki S. Prevalence of and risk factors for respiratory dyskinesia. Clin Neuropharmacol. 1996 Oct;19(5):390-8. doi: 10.1097/00002826-199619050-00002. PMID: 8889282.
5. Chiang E, Pitts WM Jr, Rodriguez-Garcia M. Respiratory dyskinesia: review and case reports. J Clin Psychiatry 1985; 46: 232-4.
6. Komatsu, Sakura MD*; Kirino, Eiji MD*; Inoue, Yuichi MD†; Arai, Heii MD*. Risperidone Withdrawal-Related Respiratory Dyskinesia: A Case Diagnosed by Spirography and Fibroscopy. Clinical Neuropharmacology 28(2):p 90-93, March 2005. | DOI: 10.1097/01.wnf.0000161637.81752.b3
7. Chiu HF, Lee S, Chan CH. Misdiagnosis of respiratory dyskinesia. Acta Psychiatr Scand. 1991 Jun;83(6):494-5. doi: 10.1111/j.1600-0447.1991.tb05582.x. PMID: 1679282.