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1.
Used in the military and medical scene the abbreviation 'NKDA' means No Known Drug Allergies.
The letters are usually sewn onto a patch and fastened to a soldier's gear, or scribbled on any plain surface of his load out such as a helmet, knee pad or raid pouch flap.
See KNA.
This soldier has O POS+ NKDA scribbled on his helmet, give him a gallon of morphine, STAT!
by Pwnkake August 11, 2008