| PIVKA | protein induced by vitamin K absence or antagonism |
|---|---|
| RCIRF | radiologic contrast-induced renal failure |
| RIM | radioisotope medicine; recurrent induced malaria; relative-intensity measure |
| SIS | semantic indexing system; serotinin irritation syndrome; simian sarcoma; simulator-induced syndrome;... |
| SIWIP | self-induced water intoxication and psychosis |