Methylphenidate lung describes pulmonary changes induced by the illicit injection of crushed methylphenidate tablets. Ritalin is a well known brand.
On this page:
Epidemiology
Methylphenidate is prescribed primarily for attention deficit hyperactivity disorder (ADHD) and narcolepsy, the latter being the only licensed indication in adults. It is in the piperidine class and is a structural analog of amphetamine. It is used globally and marketed under multiple different brands, a well-known one being Ritalin. Off-label use forms an increasingly large proportion of prescriptions 5.
Pathology
It has not been fully elucidated why emphysematous changes develop with intravenous administration of talc-containing methylphenidate 6. It has been suggested that exposure to talc either results in alveolar destruction via talc granulomatosis or that there is a secondary infection relating to talc exposure resulting in production of elastases resulting in alveolar destruction 6. However, similar emphysematous changes do not occur with intravenous administration of other talc-containing drugs, suggesting that methylphenidate itself may play a role in the pathogenesis of emphysema 6.
Radiographic features
CT
HRCT classically shows panlobular emphysema 1,4 with posterobasal predominance, out of proportion compared to any background emphysema.
History and etymology
Methylphenidate was originally synthesized in 1944 by Leandro Pannizon, a Swiss chemist working in Basel, Switzerland. His wife Marguerite, who suffered from low blood pressure, used methylphenidate as a stimulant before she played a game of tennis. His wife's nickname was Rita, and Pannizon named the drug after her 7.
Differential diagnosis
General imaging differential considerations include:
alpha-1-antitrypsin deficiency: lung changes can be almost indistinguishable on imaging 1
vanishing lung syndrome: giant bullae 3