We are providing you basic information about different medications that are safe for axolotls and natural methods for treatment of mild illness. However we do highly recommend that any time there is illness with your axolotl you seek an exotic veterinarian for professional diagnosis.
Below are some items that are good to keep on hand in your axolotl first aid kit in case your axolotl gets sick or has fungus.
It is also good practice to locate an exotic vet near you who has experience treating axolotls and keep their information available if needed, Even if you do not need one at the time, you will thank us later when you need them so you do not have to stress about finding one later on.
Note: these are just a few basic items, there are others that will treat less common illnesses you may need. A fellow breeder has axolotl First Aid kits you can purchase with pretty much everything you may need that is available over the counter: https://themottledlotl.com/products/pharmacy/
The most important things you can do to prevent illness is to cycle your tank before adding your axolotls, do weekly water changes, check you parameters weekly, clean up any uneaten food etc.
Fungus is the most common issue, it appears like a white cotton like substance that is typically on the gills of the axolotl. Salt baths will clear this up if caught early enough, but for fungus prevention you can add aquarium salt to your tank regularly. Be sure to fully dissolve it first before adding it, you can safely add 1 tablespoon per 5 gallons of water. This does not stop fungus and illness but it helps, and it adds good minerals to the water to make your axolotl happy.
Frequently check on your axolotl, make sure they are not showing signs of illness. Some things to look for are; abnormal changes to the skin, loss of weight, shrinking of the gills or gill filaments. The first think to do when you suspect your axolotl may be sick is to check your water parameters to be sure they are within the ideal ranges. Depending on severity of illness you will want to remove your axolotl from their tank and place them in a tub with 100% daily water changes until they are no longer ill. This helps keep them in clean water and so you can better monitor them.