A Rare Case of Domperidone-Induced Acute Dystonia in a Young Adult Due to Consumption of Combination Drug (Proton Pump Inhibitors With Domperidone) and Its Possible Pathomechanism.

Globally, a substantial number of people are tormented by dystonia. Domperidone, a D-2 receptor antagonist acts outside the blood-brain barrier in the brain stem as well as on the gastrointestinal tract. In India, domperidone is conveniently obtainable over the counter as a combination drug with proton pump inhibitors (PPIs) for dyspepsia and gastro-esophageal reflux disease. We present a rare case of domperidone-induced acute dystonia in a young adult presented within 72 hours after consuming two oral doses of this combination drug (PPIs with domperidone) for dyspepsia. Drug-induced extra pyramidal symptoms (EPS) are often misdiagnosed as some psychiatric condition and undoubtedly its expeditious diagnosis staves off unnecessary investigations and ameliorates prognosis. Our case ignites alertness amongst practitioners in India over the judicious use of PPIs with domperidone as the latter may trigger EPS. Such combination drugs can be prescribed if absolutely mandatory by the treating physician. The possible pathomechanism of this hyperkinetic motor phenomenon, perturbing the equilibrium of the cortical-subcortical circuit and resulting in an overflow of muscular activity, is attempted to be explained here, although the explicit mechanism is still blurry.