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Doctoring is a type of work performed by colonists assigned as a doctor in the Work menu. The Medicine skill is required and is the primary factor for success. Colonists incapable of Caring cannot perform doctor tasks.

Doctoring includes treating injuries and diseases, performing surgical operations, and taking care of patients (entertaining and feeding). How well a colonist performs in doctoring mainly depends on their medicine skill and medicine used, but their physical well-being plays an important role too: A healthy colonist with a lower medicine skill will perform better at doctoring than a colonist with a missing arm or eye and a higher medicine skill. Similarly, a doctor on consciousness-reducing drugs won't perform as well as a sober doctor. The speed at which a doctor performs medical operations is shown by the Medical Operation Speed stat.

Doctors can heal other colonists, guests, prisoners or animals and will prioritize life-threatening wounds and illnesses before tending minor conditions.
They can treat themselves at 70% effectiveness. Disabled by default, the self-tend option can be enabled on Health | Overview.


The Medicine skill is the center skill of doctoring in RimWorld. It directly multiplies the treatment quality as well as surgery success chance and healing speed before other factors are taken in. All values in this table take post-processing into account where necessary.

  • Doctor Level 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
    Base Treatment Quality 20% 30% 40% 50% 60% 70% 80% 90% 100% 105% 110% 115% 120% 125% 130% 135% 140% 145% 150% 152.5% 155%
    Base Healing Speed 40% 46% 52% 58% 64% 70% 76% 82% 88% 94% 100% 106% 112% 118% 124% 130% 136% 142% 148% 152% 160%
    Base Surgery Success Chance 20% 30% 40% 50% 60% 70% 80% 85% 90% 92% 93% 94% 95% 95.5% 96% 96.5% 97% 97.5% 98% 98.5% 99%

    The following table documents a few of many possible combinations of how factors play into a colonist's performance at doctoring (needs updating for A17):

    Colonist Medicine Skill Base Treatment Quality Manipulation [1] Sight [2] Final Treatment Quality [3]
    A [4] 6 80% 100% 100% 80%
    B [5] 18 200% 60% 30% 62.72%
    C [6] 3 50% 190% 140% 89.6%
    D [7] 11 130% 50% 100% 71.5%
    1. 90% importance in treatment quality, effective up to 140%
    2. 70% importance in treatment quality, effective up to 140%
    3. To 2 decimal places
    4. Healthy, practitioner in medicine
    5. Bad back, frail, and cataracts, visionary in medicine
    6. Fully bionic trauma savant, basic familiarity with medicine
    7. Missing an arm, strong expert with medicine
  • Medicines

    Medicine is used to improve the results of doctoring, therefore improving recovery from injuries and disease, and also allowing the performing of surgery. Another perk to using medicine is that medicine is typically able to heal multiple low severity injuries (up to max of 20 damage worth of severity), which is something that 'dry-bandaging' can't do.

    There are currently three types of medicine in RimWorld: the organic herbal medicine, the bog standard medicine, and the coveted glitterworld medicine - in order from least potent to most potent.

    In Alpha 17 it is possible to change the default healthcare given to pawns. Defaults to best meds for colonists and herbal meds for everybody else.

    Treatment Options

    Five treatment options are available; none at all, doctor care, herbal medicine or worse, regular medicine or worse, or best quality medical care.

    For prisoners and guests the default is herbal medicine; colonists default to best care available.

    In the early game, however, it is ideal to set the medical policy so that all pawns on the map only get basic doctor treatment. This allows precious medicine to be stockpiled for emergencies an operations rather than wasted on minor injuries.

    No medical care

    Somewhat straightforward, this option prevents pawns from receiving any sort of medical care. This will leave them to succumb to their wounds, or die of diseases without anyone to treat them.

    As doctor care does not require any medicine, this option is not recommended unless your intent is to let the pawn die.

    Doctor care

    Sometimes when supplies are short, or you need to save your stocks of medicine for better purposes, doctors will attempt to improvise a treatment. Note that it is not possible to do surgeries without medicine, and treatment is much slower than with any form of medicine, especially being unable to treat multiple wounds in a single treatment. Expect many infections from the poor treatment quality.

    Attributes Medical Potency Market Value Mass (kg)
    Values 30% N/A N/A

    Treatment Quality

    Doctor Level 0 3 6 9 12 15 18 20
    Base Avg. Quality 6% 15% 24% 31.5% 36% 40.5% 45% 46.5%
    Base Surgery Success - - - - - - - -

    Herbal Medicine

    Herbal medicine.png
    Herbal medicine is an organic medicine which can be grown from healroot , or purchased from tribal traders. It is not very powerful, and its best application is in treating injuries, the flu, and chronic diseases - but it can be good at treating more severe diseases when used by a skilled and/or enhanced doctor. It's not recommended to use herbal medicine for surgery, but you might just about be able to get away with it if your surgeon is fully bionic and of a very good skill level (at least level 12), but don't expect any miracles.

    Attributes Medical Potency Market Value Mass (kg)
    Values 60% 12 0.35

    Treatment Quality

    Doctor Level 0 3 6 9 12 15 18 20
    Base Avg. Quality 12% 30% 48% 63% 72% 81% 90% 93%
    Base Surgery Success 12% 30% 48% 55.2% 57% 57.9% 58.8% 59.4%


    Standard medicine is the benchmark of medical treatment solutions, and is also producible at a drug lab by combining herbal medicine, neutroamine, and cloth. It can additionally be purchased from outlanders and orbital traders, and is occasionally dropped by pirate raiders and mercenaries.

    Medicine is best used for treating severe injuries or illnesses. It also works good enough for most surgeries, though the risk of failure is still present. Odds can be improved by as little as a shot of go-juice or luciferium for boosted consciousness.

    It's not the best idea to excise cancerous growths using ordinary medicine due to its 0.7x success factor and 25% death chance on failure- unless your surgeon has at least a surgery success chance of 128.5% (achievable with a pair of bionic arms) - which translates to a roughly 90% success chance.

    Attributes Medical Potency Market Value Mass (kg)
    Values 100% 18 0.5

    Treatment Quality

    Doctor Level 0 3 6 9 12 15 18 20
    Base Avg. Quality 20% 50% 80% 100% 100% 100% 100% 100%
    Base Surgery Success 20% 50% 80% 92% 95% 96.5% 98% 99%

    Glitterworld Medicine

    Glitterworld medicine.png
    Glitterworld Medicine is the most powerful medicine out of the three types available, and can only be produced on high-tech Glitterworlds. Despite the high price, Glitterworld Medicine carries a value which no other medicine can carry: enhanced medical potency. Naturally, due to the cost, Glitterworld Medicine isn't worth the price for treating trivial diseases or injuries - but it makes surgery significantly easier, and allows even mediocre doctors to guarantee success in operations.

    Whether it be bringing somebody from the jaws of death from the plague or excising cancerous growths, or installing bionics: Glitterworld Medicine is your answer. Injuries and more secure situations with diseases: ordinary medicine will cut it, or even herbal (especially for the former).

    Attributes Medical Potency Market Value Mass (kg)
    Values 160% 100 0.5

    Treatment Quality

    Doctor Level 0 3 6 9 12 15 18 20
    Base Avg. Quality 32% 80% 100% 100% 100% 100% 100% 100%
    Base Surgery Success 32% 80% 100% 100% 100% 100% 100% 100%


    Basic medical work involving tending to wounds and illnesses. Treating wounds stop them from bleeding and reduce the chance of infections, while tending to illnesses slows them down allowing your colonists' immune systems to catch up and pull ahead.

    Each individual treatment can have any quality from 0 - 100%. Higher quality makes infections less likely and slows down illnesses more.

    After each treatment there will be text feedback showing the wound/illness tended and the quality of the treatment. Only 1 injury will generate feedback at a time even if multiple are treated at once.


    Surgery is a medical operation which involves removal and addition of body parts, or excising carcinomas. Any doctor can perform most types of surgery (excising carcinomas requires 10 medical skill), and herbal medicine is the minimum required medicine for most surgical operations, although it's not advisable to use herbal medicine in surgery unless you have an exceptionally good doctor.

    Installing bionic arm.png

    Available targets

    Surgeons can perform surgery on colonists, prisoners or guests. Performing any kind of violating surgery (such as organ removal) on guests will anger the faction.
    Tamed animals can be operated on as well, though there are limited options. Downed non-tamed animals can also be operated on once dragged to an animal sleeping spot.

    Surgeons can also perform a 'medical' operation on downed mechanoids to remove body parts and to shut them down for good.

    Success chance

    Surgery success chance is determined by several factors: The Surgeon's Medicine skill, Manipulation, Sight (until 100%), Room Cleanliness, and Medical Potency of the Medicine used.
    Outdoors, the success factor is always 60% no matter how clean the surroundings are.

    From Beta 18 onwards all surgeries have a minimum 2% chance of failure no matter how good everything is.

    The formula (simplified from the game's code) for the room cleanliness' effect on surgery success chance is effectively as follows:
    C = 0.6 + (0.9 * ((c + 5) / 10))
    if C < 0.6, then C = 0.6
    or if C > 1.5, then C = 1.5

    Where C is Room Cleanliness Factor; and c is room cleanliness.

    Surgery success chance is measured based on the medical bed/ sleeping spot's location.

    The basic surgery success chance formula is as follows:
    S = (D*M)*C

    Where S is Actual Surgery Success Chance; D is Doctor's Surgery Success Chance; M is Medical Potency; and C is Room Cleanliness Factor.

    For example, we have John, a healthy doctor with a medicine skill of 5, installing a bionic arm on a fellow colonist. His base success chance is 70%, and he is using regular medicine, with a potency of 100%. The hospital in use has a cleanliness stat of 0 with clean wood floor.

    If we plug in the numbers, we have to split the equation into two parts: room cleanliness, and getting the actual, surgery success chance.

    • C = 0.6 + (0.9 * ((0 + 5) / 10)) = 1.05
    • S = (0.7 * 1) * 1.05 = 0.735

    So John only has a 73.5% chance of successfully completing an operation, yikes!

    Keep in mind that this will be further affected by the success chance of the particular operation being performed - inherently difficult operations like removing a carcinoma will be lower success chance, easier ones like harvesting organs will have a higher success chance, and in the case of anaesthetize and especially euthanize by cut, only doctors who are both incompetent and unlucky will ever fail them. To find out the success chance of a specific operation, multiply the result from the pervious formula by the surgery success chance in the info tab for that operation

    Surgery failure

    If a surgery fails then the colonist will take damage, and materials (including prosthetics) will be wasted. For lesser failures, damage is concentrated near the site of surgery, while for the aptly named ridiculous ones they can be found anywhere in the body.

    There are 3 kinds of surgery failure in-game.

    • Minor: Deals a little damage, and will not destroy any body parts.
    • Catastrophic: Deals great damage, and usually destroys body parts outright.
    • Ridiculous: Deals great damage scattered across the entire body.

    In addition, each surgery has a death on failure chance, meaning that when it fails it is possible that the colonist instantly dies.

    Doctoring strategies

    You will often need to make the most out of the doctors you have, to ensure maximum doctoring efficiency and colonist survival rate/ well-being.


    You should have doctors prioritize treating patients according to their illness/infection/injury severity.

    1. Bleeding colonists should receive priority care as they may bleed to death or receive nasty infections. Always prioritize colonists closer to death.
      • Colonists about to die (<1 hours until death) are generally not worth saving unless you have extremely good bionic-enhanced doctors that can reach and patch them up in time.
        • Strip them to recover their clothes so they won't receive the deadman's apparel debuff. How you will deal with the dead colonist is up to you.
      • Colonists that are very close (1-4 hours till death) to dying should have the best doctors care over them.
      • Colonists with around 5-8 hours before death can be treated by regular doctors, or by good doctors without medicine.
      • Colonists with 12 hours or more till death can wait.
    2. Colonists sick with deadly diseases should also receive priority care, especially those with wound infections or the plague.
    3. Non-bleeding colonists aren't in a great risk of both infections or blood loss; they should be put on the bottom of your priority list.

    If left undirected, doctors will automatically tend in order:

    1. The nearest patients that will die from blood loss in 18 hours
    2. The nearest human patients
    3. Himself/herself if self-tend is enabled
    4. (Feed patients in bed)
    5. (Surgeries)
    6. (Rescue downed colonists and pets by taking them to bed)
    7. The nearest non-human patients

    Note that this automatic priority does not take into account the overall severity and lethality of all the illnesses, infections, and injuries afflicting patients, other than the death from blood loss in 18 hours limit. Nor does it prioritize colonists over prisoners or visitors. If imminent death is a concern, it's not a good idea to rely on this default behavior.

    Medicine allocation

    Doctors will always tend to use the best medicine possible by default. To counteract this, set colonists' healthcare to Normal medicine or worse. Switch to Glitterworld medicine only if the colonist is down with a fast-working illness and you don't have a decent doctor on board, or they are about to receive a difficult operation.

    You can also manually forbid medicine so they will be forced to use lower-tier medicine, so you can save your better medicine for later.

    You should try to split your medicine apart into many stacks. If a doctor is about to treat a patient and someone else is getting medicine from a stack, your doctor will use medicine from another stack, or if there's none, he will try to dry-bandage the injured colonist. To combat this, you can draft doctors to go towards the medicine stacks, and manually un-draft and assign them to treat colonists when a doctor is finished taking the medicine.


    Medicine should always be put near the hospital. Don't put them right inside the hospital as it reduces beauty unless you're willing to build a shelf to put them in. If you're anticipating the need for a treatment, have a doctor stand near your stocks of medicine. You can immediately get the doctor to heal them without having to have him go to the medicine storage and back, saving time. If using primarily herbal meds then it is best to cool the room. It will rarely be necessary to freeze them, but it could make the difference


    The cleanliness rating of a room has a major impact on the infection chance of a pawn, and a comparatively minor, but still significant impact on the success chance of surgery. It also affects other things, like research speed and food poisoning chance

    Infection When a bed is set to be medical, selecting it shows the infection chance modifier of the room. The overall chance of infection is affected by tend quality, and then multiplied by the aforementioned number. Any bed, no matter what it is, has a 100% modifier on infection when outdoors, and only an incredibly dirty room can get close to this number. However, even at an 80% modifier, wounds tended by an unskilled doctor using herbal meds is likely to be around 10-20% infection chance per wound. Averting death by a thousand cuts will quickly become agonizing death by 100 infections in such circumstances.

    It is much better to make the hospital as clean as possible. Start by covering or removing all natural floors (dirt, sand etc. but excluding stone) and ensure that the hospital is cleaned before tending to pawns. Keep all pawns, especially animals out to keep the room as clean as possible. Infection chance multiplier will likely become around the 40-50% mark or even lower. Next, unlock sterile tiles. A room with 0.6 cleanliness can have multipliers near 30%. To see the cleanliness of rooms, toggle on the room stats view on the bottom right corner and then mouse over the hospital (or any other room for that matter). Dirt, animal filth among other things drastically reduces cleanliness, and it also reduces beauty. This makes it possible to locate and prioritize cleaning through the beauty view. Remember to clean before the treatment when possible.

    One of the most difficult things about keeping a hospital clean is bleeding. Bleeding colonists will leave blood on the floor (makes sense right?), and blood reduces cleanliness. Someone hemorrhaging to death may create 4 or 5 blood splatters on the floor in a very short time, and if this is happening to multiple colonists after a disastrous raid, your doctor alone may not be enough to keep the room clean. Bring in another colonist or two to clean up after other patients awaiting treatment. What is important is the cleanliness at the time of treatment.

    Other things like the presence of hospital beds and better medicine/doctors can reduce infection chance to next to nothing, and make it a non-issue when it does occasionally arise.

    To-do List (temporary)

    To-do list for this page (not in order, feel free to contribute):
    • Sanitation: How it affects surgery, and infection likelihood.
      • Physical well-being's effect on this too

    Version History

    • 0.9.722 - Surgery can fail now, sometimes catastrophically. Failure chance is related to the surgeon’s medical skill and the quality of the medicine.