Natural Healing
A wounded creature can recover hit points by getting a good night’s rest and adequate food. Provided they are warm, fed, and comfortable, they regain hit points each morning equal to their experience level, or equal to their hit dice if they are NPCs.
Frail creatures do not recover hit points through natural healing. They must cure their Frail condition first or rely on medical pharmaceuticals. Removing the Frail condition requires a full week of bed rest and the medical attention of someone with at least Heal-0 skill and a medkit. Frail victims without this level of medical care must make a Physical save after a week; on a failure they die sometime in the next week, while success means they lose their Frailty after another month of rest.
First Aid
Modern combat medicine can patch up victims in a hurry, albeit at a cost to their physical resilience. By spending one minute patching up an ally with a medkit, a healer can heal 1d6 points of damage plus their Heal skill. If they lack any Heal skill at all, they restore 1d6-1 points. Each such application of first aid adds one System Strain to the target. First aid can restore hit points to a Frail target, but it cannot remove their Frailty.
Five minutes is enough time for a medic to apply as much first aid as is wanted to the rest of their team.
Poisons and Diseases
Most toxins force a victim to make a Physical saving throw to resist their effects or mitigate their harm. Weak perils might grant as much as a +4 to the saving throw, while dire threats might apply a -4 penalty.
If the save is failed, the poison or disease takes hold. Most poisons act quickly, inflicting hit point damage, adding System Strain to the target, or applying long-lasting penalties. Diseases can have a slower onset but often apply the same sort of harms.
A medic who gets to a poisoned person within a minute of the poisoning can use a medkit to give them a better chance to resist. They may add twice their Heal skill level to the victim’s saving throw roll, or +1 if they have only Heal-0 skill. Specialized antitoxins may be able to neutralize such poisons entirely.