the doctors do not need to have any stock, they write the prescription the patient takes it to their local Boots or Lloyds chemist/pharmacy and pay the NHS fee (unless over 60 etc).
The doctors need to know about it so they can prescribe it - that's where marketing is very very important
as mentioned roughly 1/5th of all stores already had the product on shelves and since most high streets in the UK have at least 2 pharmacies they may only be in half as but they were ordered in Q1 so will show in May 15ths numbers
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