| RAS | rapid atrial stimulation; recurrent aphthous stomatitis; reflex activating stimulus; reliability, av... |
|---|---|
| RASS | rheumatoid arthritis and Sjogren syndrome |
| RAT | repeat action tablet; rheumatoid arthritis test |
| RhA | rheumatoid arthritis |
| SARA | sexually acquired reactive arthritis; Superfund Amendments and Reauthorization |