Health Canada flags possible weight-loss risk for under-6s on ADHD stimulants

Health Canada says children under six who take central nervous system stimulants for ADHD off-label may face a greater risk of weight loss than older children on the same dose, and it will work with manufacturers to update Canadian product monographs accordingly.

The finding is set out in a Summary Safety Review on the Drug and Health Products Portal covering amphetamine-, dextroamphetamine-, lisdexamfetamine-, mixed-salts amphetamine- and methylphenidate-containing ADHD medicines — brands that include Adderall XR, Biphentin, Concerta, Dexedrine, Dyanavel XR, Foquest, Jornay PM, Quillivant ER and Vyvanse, plus generics. In Canada these drugs are authorized for ages six and up; preschool use is off-label even though some jurisdictions abroad authorize certain amphetamine products from age three. Weight loss is already labelled for approved age groups. After a U.S. FDA communication and label updates on extended-release stimulants in younger children, Health Canada reviewed foreign regulatory information, Canada Vigilance reports and scientific literature.

Fourteen cases of weight loss in under-sixes (12 Canadian, two international) were identified but did not individually meet criteria to confirm a causal link. Taken with published studies and foreign-agency data, however, the review concluded there is a possible increased risk versus older children at the same dose. Health Canada is not telling families to stop treatment on their own; it is adding the warning so clinicians can weigh growth monitoring when prescribing off-label. Consumers and professionals are encouraged to report suspected side effects through the Canada Vigilance Program. Coverage in Canadian Healthcare Network and Canada News Media places the review alongside Health Canada’s September Health Product InfoWatch bulletin.

This article is for information only and is not medical advice. Talk to a qualified clinician before starting, stopping or changing any medication.

Sources: Health Canada — Summary Safety Review, CNS stimulants and weight loss under age 6; Canadian Healthcare Network; Canada News Media.