Rad-X (Fallout 3)

Rad-X is an anti-radiation chem to be taken before exposure (unlike Rad Away, which removes the effects of radiation after a person gets irradiated). It has no known side effects.

Fallout 3
Rad-X is an antiradiation chemical that can majorly reduce the danger of irradiated areas. When combined with an Advanced Radiation Suit, even at moderate medical skill can create near-immunity to radiation.

In general, Rad-X is best used in heavily irradiated areas, as that is where the most benefit can be seen. It is reasonably common, as such it can frequently used as the situation warrents.

Appearances
Rad-X appears in all Fallout games.