Background & Aims
Pregabalin has been recommended as a first-line treatment for neuropathic pain, such as diabetic peripheral neuropathy, post-herpetic neuralgia, spinal cord injury, and radiculopathies. The most commonly noted adverse effects of pregabalin include sedation, dizziness, peripheral edema and dry mouth. Oculomotor manifestations associated with pregabalin have rarely been reported. Positional upbeat nystagmus caused by pregabalin has not been reported. Herein, I report a case of patient who developed vertiginous giddiness and upbeat nystagmus during treatment with pregabalin.
Methods
Case Report
Results
A 36-year-old female patient with recent lumbar intervertebral disc surgeries was admitted to my department for inpatient rehabilitation and pain management. She underwent left L4/5 posterior decompression for left foot drop and numbness 5 months prior to this admission. She underwent L4 to L5 posterior decompression and discectomy for right lower limb pain and numbness 3 months prior to this admission.
She still complained of severe low back pain and right lower limb radiating even after the second spine surgery. She had been treated with pregabalin 150-150mg daily since the second spine surgery. Pregabalin dose was increased 150-50-150mg daily by pain team 20 days prior to this admission to optimize pain control.
She complained of severe vertiginous giddiness during turning her head to left and getting up from bed on the day of admission. Bilateral severe upbeat nystagmus was noted during roll test. Upbeat nystagmus was also noted on left side-lying test. The laboratory tests were unremarkable. Brain magnetic resonance image was normal as well.
On suspicion of adverse effect of pregabalin, dose of pregabalin was reduced to 150-150mg daily. Vertiginous giddiness and upbeat nystagmus were resolved within 2 days of reducing pregabalin dose.
Conclusions
The mechanisms of pregabalin related vestibulocerebellar disorder are not yet well understood. The pharmacological studies in rat model suggested that pregabalin binds to the ?2 ?-1 and ?2 ?-2 subunit of voltage-gated calcium channels, which are expressed in the brain and spinal cord. It is known that ?2 ?-1 is present in cerebral cortex, hippocampus and cerebellum, and ?2 ?-2 is concentrated in the cerebellum. Decreased excitatory inputs from brain, especially cerebellum by pregabalin may result in functional disturbance of the cerebellum.
In conclusion, this case demonstrates that pregabalin can induce vestibulocerebellar symptoms. Clinician should be aware that vestibulocerebellar adverse effects may occur with the usual dose of pregabalin and proper neurologic or vestibular evaluation is necessary to rule out other possible causes of symptoms and signs.
References
1.Nakashima H, Kanemura T, Ando K, Kobayashi K, Yoneda M, Ishiguro N, Imagama S. Is pregabalin effective against acute lumbar radicular pain? Spine Surg Relat Res 2019; 3(1): 61-66
2.Toth C. Pregabalin: latest safety evidence and clinical implications for the management of neuropathic pain. Ther Adv Drug Saf 2014; 5(1): 38-56
3.Choi JY, Park YM, Woo YS, Kim SU, Jung JM, Kwon DY. Perverted head-shaking and positional downbeat nystagmus in pregabalin intoxication. J Neurol Sci 2014; 337: 243-244
4.Ekinci AS, Ciftci S, Caus B, Aydogdu I. Could pregabalin cause oculomotor symptoms in lower dose? A case with down beat nystagmus as a side effect. Acta Neurol Belg 2016 DOI 10.1007/s13760-016-0735-x
5.Jeong SH, Kim YS, Lee JH, Jo H, Lee AY, Kim JM. Transient positive horizontal head impulse test in pregabalin intoxication. J Epilep Res 2015; 5(2): 101-103
6.Li Z, Taylor CP, Weber M, Piechan J, Prior F, Bian F, Cui M, Hoffman D, Donevan S. Pregabalin is a potent and selective ligand for ?2?-1 and ?2?-2 calcium channel subunits. Euro J Pharmacol 2011; 667(1-3): 80-90
7.Dolphin AC. The ?2 ? subunits of voltage-gated calcium channels. Biochimica et Biophysica Acta 2013; 1828: 1541–1549
8.Ali S, Hassan WA. Pregabalin induces pathological changes in cerebrum and cerebellum of albino rats. Res Square 2021 DOI 10.21203/rs.3.rs-778481/v1
9.Rietjens SJ, Sikma MA, Hunault C, de Lange DW, Hondebrink L. Pregabalin poisoning: Evaluation of dose-toxicity relationship. Br J Clin Pharmacol 2022; 88:1288-1297
Presenting Author
Jongmoon Kim
Poster Authors
JONGMOON KIM
Medical Doctor
Tan Tock Seng Hospital
Lead Author
Topics
- Treatment/Management: Pharmacology: Adverse effects