My advice would be, in the first instance, to call the chemist who dispensed your prescription, and see if you can talk to the pharmacist and ask their advice.
If the pharmacist is unable to advise you, then
do not start the Sitagliptin without speaking to your GP first. I assure you from experience that an extra day without it will make no difference in the long term. Personally, I would rather not take it without speaking to my GP first, than take it and end up with pancreatitis all over again! It is always best to err on the side of caution.
Do let me know how you get on!
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