Here is a fascinating 2016 article on the use of Benzedrine, colloquially known as Wakey-Wakey pills, by the RAF. As most people who follow this website will know, operational bomber aircrew sometimes used such pills to keep themselves awake during their long and dangerous night operations.
In November 1942, Britain’s Royal Air Force (RAF) approved the use of amphetamine sulphate, known by its brand name, Benzedrine, for use on operations by its aircrews. The substance, a powerful stimulant with the ability to promote both wakefulness and well-being, had been subject to a strict policy of prohibition in the RAF since September 1939. The decision to reverse this policy was the culmination of a lengthy process within the Service, driven by laboratory and operational testing in conjunction with scientific, medical and military debate.
The Royal Air Force, Bomber Command and the use of Benzedrine Sulphate: An Examination of Policy and Practice during the Second World War. James Pugh, University of Birmingham. Copyright: Author / SAGE / Journal of Contemporary History.