RadAway is an intravenous chemical solution that bonds with radiation particles and passes them through the body's system. It takes some time to work, and is also a potent diuretic.
It cannot be used to keep away from, or resist radiation when entering radioactive areas like it's relative namesake Rad-X, but is instead used for after receiving radiation to purge some of it from the body.
On top of being addictive, it has several adverse effects, most notably headaches, stomach pains, and hair loss.
In Fallout: New Vegas, RadAway is much less common as most shops only have 1 to 3 in stock, if any at all, though it is often stocked by doctors. However, areas of significant radiation are far less prevalent, so the need for RadAway is reduced.
RadAway heals radiation over time in Hardcore mode, instead of instantly in Normal Mode.
RadAway glows even brighter than in Fallout 3, making it easy to locate.
After taking 20 doses of Rad-Away, you will be granted the Free Radical Perk, enhancing the effectiveness of RadAway.
RadAway bears a striking resemblance to a real-world unit of fresh frozen plasma (which would be a viable medium for such a chemical).
Behind an average locked door in the Vault 3 recreation area there is a stockpile of many medical supplies including 3 RadAway.
Camp Searchlight contains 8 RadAway: 1 on a shelf left of the terminal in the NCR storage Room 2 on a shelf within the first room of the firehouse. 3 in a duffle bag next to a bed located on the second floor of the firehouse. 2 in the broken lockers within the bathroom of the firehouse second floor. You can only access the fire house if you have activated the quest Wheel of Fortune.
After completing the quest High Times for the Followers, you can speak to Julie Farkas and you may choose to get a stimpak, RadAway or a Fixer. You can get one item from her per day.
Dead Money An effectively unlimited supply of RadAway can be obtained from Sierra Madre vending machines, provided the player has a sufficient amount of chips and has installed the Radaway Holotape.