Adoctor wrote a prescription stating, “8 mg tab qd.” which describes what the patient is supposed to do?

Explanation:

A doctor wrote a prescription stating '8 mg tab qd'.

In this sentence there are 3 parts. One is defining the potency of the tablet, i-e, 8 milligram. Second is the Tablet, which would be the name of the tablet, which could be say Ponston. And the third one is QD, which is derived from latin word, 'quaque die', which means one a day.

So the sentence prescribed by doctor means, take 8 milligram of ponston tablet once in a day.  

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