The CIA has privately advised its workforce that taking an anti-malarial drug touted by President Trump and some of his supporters as a promising treatment for the novel coronavirus has potentially dangerous side effects, including sudden death.

The warning, featured on a website for CIA employees with questions related to the spread of covid-19, came in late March after public discussion — and promotion by the president — that hydroxychloroquine, administered in concert with the antibiotic azithromycin, might prove effective against the disease.

The politically charged debate over hydroxychloroquine — medical experts say there’s still no conclusive evidence it does what Trump has suggested — underscores a recurring phenomenon in this administration, in which the president stakes out a very public, sometimes controversial position on a subject only to have agencies within the government chart a different, more cautious approach.