What it means
Intrathecal means into the fluid around the spinal cord, through a needle or catheter in the subarachnoid space, as for spinal anesthesia or some chemotherapy. ISMP lists "IT" as an error-prone abbreviation because it has been mistaken for intratracheal, intratumor, intratympanic and inhalation, and giving a drug by the wrong route can be fatal. Write "intrathecal" in full.
For the nurse
Contact the prescriber if an order uses "IT." Medications given into the spinal fluid are high-alert, so check the route with a second nurse as policy requires.
Related terms
epidural anesthesia
Pain relief or numbness from an anesthetic drug given through a thin catheter into the space just outside the covering of the spinal cord.
subarachnoid space
The space between two of the thin membranes that cover the brain and spinal cord, filled with cerebrospinal fluid.