SpaceX's federal contracts require those with security clearances, like Musk, to remain drug-free and submit to random drug tests. The NYT says Musk gets advance notice of these tests.

Elon Musk interrupted a reporter who started to ask about a New York Times story alleging he used a copious amount of drugs and travelled with a pill box that appeared to contain Adderall last year as he ramped up his donations to President Donald Trump—blasting the paper, but stopping short of denying the report.

Musk has spoken about his prescription ketamine use in the past. Last March, he told journalist Don Lemon that he uses a “small amount” of ketamine about once every other week. The ketamine, he said, is prescribed by “an actual, real doctor.”