How do I keep my hamster healthy?

What should I know about hamsters at a glance?

Hamsters are small rodents that sleep through the day and wake in the evening. The kinds kept as pets are the Syrian (golden) hamster and the smaller Chinese, Russian dwarf (Campbell's and winter white) and Roborovski hamsters.

What health problems do vets see most in hamsters?

Diarrhea (wet tail) is seen often and mites are common, according to the Merck Veterinary Manual. Overgrown teeth, cheek pouch problems and lumps also bring hamsters to the vet, and older Syrians get heart disease.

• Wet tail: diarrhea that leaves the fur under the tail wet and dirty. In young hamsters, mostly at 3 to 10 weeks old, it is often caused by the bacterium Lawsonia intracellularis, and VCA notes that hamsters may die even with early, aggressive treatment.
• Overgrown teeth: a hamster's front teeth never stop growing. When they overgrow, the Merck Veterinary Manual lists drooling, eating less and weight loss as the signs.
• Cheek pouch problems: food can get stuck in a pouch and cause inflammation, infection and abscesses, and a pouch can turn inside out and stick out of the mouth, according to Vet Help Direct. Pouch problems can come with dental problems.
• Mites: common, especially in older males, according to the Merck Veterinary Manual. A heavy infestation brings dry, scaly skin and fur loss, often over the back and rear end.
• Lumps: many growths in hamsters are benign, but lymphoma appears in older hamsters. Any lump needs a vet check.
• Heart disease: older Syrians can develop blood clots in the heart (atrial thrombosis). The Merck Veterinary Manual puts it at up to 70% of aging Syrians, at a younger age in females than in males.
• Breathing problems: these can become serious quickly in a hamster.

Do hamsters need vaccines or parasite treatments?

Hamsters don't get vaccines. The Merck Veterinary Manual says none are required or recommended, and VCA agrees. Parasites are treated when a vet finds them, not on a set schedule.

• Mites: a vet usually treats them with a product put on the skin, along with frequent cage cleaning. The Merck Veterinary Manual notes that hamster mites generally don't affect people.
• Stool tests: VCA suggests testing a stool sample for parasites at each checkup.
• Products: the RSPCA advises using only medicines a vet recommended for your hamster.

Which signs in a hamster can't wait?

Hamsters hide illness until they are very sick, so VCA treats any change from normal as a reason to see a vet right away. Call a vet who treats hamsters the same day for any of these.

• Wet tail: wet, dirty fur under the tail, watery droppings, a hunched back or a hamster that stops eating. PetMD calls wet tail often a medical emergency and advises seeing an exotics vet within 24 hours.
• Not eating or no droppings for 24 hours: both are on the emergency list for small mammals from Vet et Nous, a veterinary hospital group.
• Breathing trouble: breathing with an open mouth, or gums that look bluish grey instead of pink.
• A pouch sticking out of the mouth: a pink, fleshy mass at the corner of the mouth is a cheek pouch turned inside out. Don't try to push it back. A vet has to deal with it.
• A bulging eye: the Merck Veterinary Manual treats it as an emergency.
• Cold, limp and hard to wake: in a cold room this can be torpor. Warm your hamster slowly in your hands, never on a heater, and call your vet if it doesn't wake once warm or feels stiff.
• Weakness, seizures, poor balance or a fall.
• Weight loss: down 10% since the last weigh-in, a warning sign that needs a vet soon.

Find a vet who treats hamsters before you need one. Don't give medicines at home unless a vet says so, because some antibiotics can kill a hamster.

How do I care for a hamster day to day?

A pellet diet, a clean and calm home and a weekly weigh-in cover most of what keeps a hamster well. Stress from moving, crowding, heat, a dirty cage or spoiled food hidden in the nest makes wet tail more likely, according to PetMD.

• Food: a pelleted rat, mouse or hamster food with 15 to 20% protein, in the Merck Veterinary Manual, plus small amounts of vegetables and fruit. Treats stay under 10% of the diet. Never a seed-only diet, which VCA calls high in fat and poor in nutrition.
• Foods to avoid: the RSPCA lists grapes and rhubarb as poisonous to rodents, and advises against sudden diet changes and stale food.
• Water: fresh water always. Check the bottle every day for leaks and blockages.
• Weight: weigh your hamster every week on the same scale, one that reads grams. Vet et Nous treats a 10% loss as a warning sign that needs a vet soon. In a 30 g Roborovski that is only 3 g.
• Teeth: look at the front teeth regularly and give safe things to gnaw. VCA advises that overgrown teeth be treated by an exotics vet as soon as possible.
• Cleaning: the RSPCA suggests spot cleaning every few days and a deep clean once or twice a month, done while your hamster is awake.
• Heat and noise: keep the cage at 18 to 26 °C, away from draughts and damp. VCA notes that hamsters don't tolerate heat and need a cool spot in summer. Keep the cage away from TVs, computers and running water, whose high-pitched sounds hamsters hear.
• Handling: let your hamster know you're there before you touch it, and wake it gently. VCA says hamsters usually bite when startled or held too tightly.
• Baths: no water baths unless your vet asks for one. A shallow dish of chinchilla sand, not chinchilla dust, lets your hamster clean its coat.
• Exercise balls: the Merck Veterinary Manual warns never to leave a hamster in one unsupervised.
• Medicines: some antibiotics can be deadly to hamsters because they upset the gut bacteria, according to the Merck Veterinary Manual, and its veterinary edition names penicillin, lincomycin and bacitracin among the ones that set off this gut infection. Give only what a vet who treats hamsters prescribed.
• Checkups: VCA advises a vet visit within 48 to 72 hours of bringing a hamster home, then once a year, and twice a year once it is older.

How big should a hamster's cage, wheel and bedding be?

As big as you can manage. Legal minimums differ by country, and welfare advice goes well beyond them. These are the figures from two countries that set minimums in law (the Swiss ones are for Syrian hamsters). Ask your vet what suits your hamster.

In a study of Syrian hamsters in four cage sizes, those in small cages gnawed the bars longer and more often, and the authors judged welfare better in cages of at least 10,000 cm² (1 m²) (Fischer and others, 2007).

Whatever the size, the Merck Veterinary Manual advises a solid floor, a wheel with a solid running surface instead of wire rungs, and no cedar or pine bedding, which can be poisonous. The RSPCA adds a dark nest box and warns against nesting material that comes apart in thin strands, like cotton wool.

Can two hamsters live together?

Syrian and Chinese hamsters must live alone. The RSPCA says they aren't naturally sociable, and Austria's rules require Syrians to be kept alone.

Dwarf hamsters (Campbell's, winter white and Roborovski) can sometimes share a cage in pairs or trios, if the group formed early in life and stays calm. They don't need company to be happy. If you keep dwarfs together, the RSPCA advises:

• Check them every morning. Fights happen mostly at night and can cause serious injury or death.
• Hamsters that fought must live apart for good. Don't put them back together.
• Don't add a new hamster to a group later, and don't mix kinds or sexes.
• Give them several hiding places, so each one can hide when it wants.

How do I keep my hamster's health record?

VetVitae, a free pet health record app for iPhone, Android and the web, keeps your hamster's weight in grams and warns you when it drops 10% in a month. It logs vet visits, exams, deworming and medicines, and leaves vaccines out, since hamsters have none.

It also suggests hamster routines like Fresh water, Spot clean the cage, Change the sand bath and Quick health check, with reminders at 20:00. See small mammals in VetVitae and weight.

This guide is general information, not veterinary advice. Your vet knows your pet.

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