Brief Answer:
There are exemptions where pill imprint is not compulsory

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. The FDA requires all prescription and over the counter medicines sold in the US to have an imprint on them unless it is exempted under following conditions

(i) When the physical characteristics of the drug product make it impossible to imprint
(ii) When the medication is dispensed in a controlled health care setting (eg, in a physician's office)
(iii)When the drug is not dispensed to patients for self-administration

2. If the exemptions are not met and imprint is not there then it can be a supplement, energy pill, vitamin or herbal pill.

3. Please consult your doctor in case of any medicine without imprint before consuming.

Hope your query is answered.
Please do write back if you have any doubts.

Regards,

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