To use this you face the injured X-Com agent or stand over the body of a stunned aquanaut. Healing: Red indicates wounds. Select body part and click on the 'Heal' button. One fatal wound will be healed and health restored. Stimulant: Restores energy and revives stunned aquanauts. To revive an unconscious aquanaut you must stand directly over the body. Pain Killer: Restores the morale of wounded aquanauts.
Medi-Kit (Enemy Unknown) for more detailed information on use, etc.