Rats are prone to a variety of illnesses. It's best to have an exotic vet chosen as well as money set aside for vet bills.
If you are concerned with your rat's health, please consult a veterinarian immediately. I suggest joining the Facebook group "Real Rat Lovers Want To Know" as it's a great resource for rat health.
Porphyrin - Red discharge near the eyes and nose
Porphyrin looks a lot more serious than it actually is. It's often confused for blood due to its red coloring.
A small amount of porphyrin is not cause for alarm, but excess amounts can indicate illnesss, stress, or poor diet.
Hairless and double rex rats create porphyrin to clean their eyes from debris since they have little to no eye lashes. Mine have red rimmed eyes after each nap and they clean it right when they wake up! This is perfectly normal.
If you think your rat is creating an abnormal amount of porphyrin, schedule a vet visit in order to discover the cause.
URI (Upper Respiratory Infection) - Most common rat illness that can be fatal if left untreated
Signs: Sneezing, coughing, excess porphyrin, wheezing, lethargy, etc.
Most rats will have an URI at least once during their lifetime due to their sensitive respiratory systems or because of the disease, Mycoplasma pulmonis. All rats are born with this disease so it's important to pay close attention to your rat's health, and to treat them as soon as symptoms show.
Antibiotics such as amoxicillin and doxycycline are great for treating URIs. You can purchase these medicines in the fish department of pet stores or online at places such as DrsFosterSmith.com. A google search will give you dosing instructions.
URIs normally require a vet visit.
Mammary Tumor - Fast growing masses, most commonly in females
Mammary tumors form on the stomach, chest, groin, or armpit areas. They are fast growing and take the blood and nutrients from a rat, causing them to become skinny. Mammary tumors are so common that nearly all rats will get at least one in their lifetime.
Surgical removal is a great option for rats that aren't too old and are still in good health. This is a good way to extend the life of your rat, although more tumors can always grow. The second option is to let your rat live the remainder of their life with the tumor. You will need to take them to a vet to be euthanized if your rat becomes lethargic, has a difficult time walking, or if painful wounds form on the tumor.
The best way to avoid mammary tumors are proper breeding or getting your female rats spayed.
Mites - 3 types of living parasites commonly effect rats: fur mites, ear mange mites, and blood sucking mites
Signs of mites include hair loss, scabs, crusty spots, itching, etc.
Mites are invisible to the naked eye so you must pay attention to any changes in your rat's fur, ears, or tail.
I see many pictures of rats with reddish, brown spots on their ears. This is a sign of mites and if not treated, will continue to worsen until the ears are crusty and jagged. These mites burrow under the skin.
You can treat mites and other parasites (fleas, lice, etc) with Revolution for kittens or cats. Otherwise, a vet visit is necessary. Treat all of your rats as mites are easily transmitted from rat to rat.
Beginning Stages of Mange Mites
Small spots on the ears
Mites if left untreated
Lice - Species specific lice suck the blood of your rats and may transmit internal parasites or diseases
Signs of lice include itching and hair loss.
You can see lice and their eggs (nits) with your naked eye.
Fleas - Any fleas (dog and cat) can transfer to your rats and may transmit internal parasites or diseases
Signs of fleas include itching and scabs. You can see fleas and their dropping (black spots).
Treat external parasites with Moxidectin or Ivermectin. You may also use kitten or cat Revolution. A vet visit may be necessary for a prescription.
Bumblefoot - A bacterial infection on the foot that looks like a wound or inflamed bump. This painful infection must be treated immediately to avoid further infections that can lead to death.
Bumblefoot is easy to recognize and it is found most commonly on one or both back feet. It appears as an abrasion or abcess that can include crusting, blood, or puss.
Bumblefoot may be caused by wire flooring or rough bedding that creates scratches on our rat's feet (which is why all wire or mesh shelves should be covered with fleece). An unsanitary cage and wet or dirty bedding are common causes of this bacterial infection.
I recommend scheduling a vet visit as it's often difficult to treat bumblefoot successfully. Your rat may need antibiotics, an antibiotic ointment, and their feet cleaned or soaked everyday until the infection is no longer present.