| IMEM | improved minimum essential medium |
|---|---|
| IPO | improved pregnancy outcome |
| ITM | improved Thayer-Martin [medium]; intrathecal methotrexate; Israel turkey meningoencephalitis |
| OCP | octacalcium phosphate; ocular cicatricial pemphigoid; oral case presentation; oral contraceptive pil... |
| OET | oral endotracheal tube; oral esophageal tube |