How Long Can a Hamster Go Without Food?

No veterinary or welfare source gives a safe number of days for a hamster to go without food, so this page does not give one. What the sources do say is that a hamster eats several small meals a day, does not carry enough body fat to go long without food, and can slip into torpor if it gets cold. A hamster that starts eating less than usual needs a call to the vet right away, and a hamster you are leaving for a trip needs a person who checks its food and water every day.

How Long Can a Hamster Go Without Food?

The RSPCA says domestic hamsters "do not have enough fat reserves to survive without food for prolonged periods of time." It makes that point while explaining why a hamster should live indoors. A cold hamster can drop into torpor, a hibernation-like state, and torpor is the dangerous part when there is no food to draw on. The Louisiana Veterinary Medical Association adds that hamsters do not fatten before hibernation, so a hibernating hamster has to wake up from time to time to eat.

The RSPCA, PDSA, and MSD Veterinary Manual pages on hamster care give no count of days, so this page gives none. Each one asks for water to be available all the time, and the RSPCA and PDSA both describe checking food and water every day. A hamster that has run out of food is a problem to fix the same day. A hamster that has stopped eating with food in the bowl is a different problem, and the section on signs that need a vet covers it.

How Much a Hamster Eats and Drinks Each Day

The Louisiana VMA puts a hamster's daily food at about 10 to 12 grams per 100 grams of body weight and daily water at about 8 to 10 milliliters per 100 grams. It says hamsters eat several small meals about 2 hours apart. The table applies those figures to the adult Syrian weights the same source lists, 85 to 150 grams across males and females.

The MSD Veterinary Manual says a commercial rat or mouse pellet with 15 to 20 percent protein meets a hamster's needs, and that treats should make up no more than 10 percent of the diet. The RSPCA's page on hamster's daily diet covers the rest of the menu, and the National Research Council's chapter lists the nutritional needs of the hamster in detail. For pellet picks, see our guide to the best hamster foods, and for other small pets see appropriate food for small pets.

Feeding Habits and Food Stashes

Hamsters carry food in their cheek pouches to the nest or a hiding place, where they eat it or stash it for later, the RSPCA says. The MSD Veterinary Manual says they hide food in the cage too. An empty bowl can mean the food has moved, so check the nest and the bedding before you decide how much your hamster is eating.

The RSPCA suggests scattering or hiding food around the cage so a hamster can forage, and PDSA gives the same ideas: scatter pellets, bury them in the bedding, or hide hay and pellets in paper bags and cardboard tubes. PDSA's daily spot clean includes removing uneaten food, so that is also the moment to find any fresh food left in a stash.

Water for a Hamster

Water gets its own rules. The RSPCA says hamsters need a constant supply of fresh, clean water, preferably from a bottle with a valveless sipper tube, and that the bottle should be checked every day for leaks or blockages. It adds that hamsters cannot apply strong suction, so a traditional ball-valve sipper can be hard for a young, old, or sick hamster to use. The MSD Veterinary Manual says to clean the bottle or bowl often, usually every day, and to make sure the sipper is not blocked.

A full bottle can still be blocked, so press the tip and watch for water. The sources give no number of days a hamster can go without water. They say it must always be available.

Cold, Torpor, and a Hamster That Will Not Move

The MSD Veterinary Manual says to keep a hamster's cage at about 64 to 79 F (18 to 26 C). PDSA suggests a steady 18 to 21 C (about 64 to 70 F), away from draughts and direct sunlight, and warns that a cage that gets too cold can send a hamster into torpor. PDSA says torpor typically lasts from a few hours to a few days.

If you think your hamster is in torpor, PDSA says to check that the room has not fallen below 20 C (68 F). If it has, raise the temperature gradually to help the hamster wake. When you cannot tell whether a hamster is in torpor or has died, PDSA lists three checks: watch for breathing, gently feel the chest for a heartbeat, or gently stroke it to see whether the whiskers twitch.

When a Hamster Stops Eating

The RSPCA says to keep a close eye on how much a hamster eats and drinks. If it starts eating less, its droppings become moist, or its hind-quarters become soiled, talk to your vet immediately. PDSA gives the same instruction for any change in behavior or appearance. The sources name these causes.

• Wet tail. The MSD Veterinary Manual says signs include wet fur around the tail, low energy, poor appetite, and weight loss, and that stress from travel or diet changes can make diarrhea more likely. PDSA adds dehydration and sometimes sudden death.
• Teeth. PDSA says overgrown teeth can prevent a hamster from eating and cause pain, weight loss, and drooling. The RSPCA says that if one incisor is damaged the other keeps growing, which can eventually stop the hamster eating.
• Lung infection. The MSD Veterinary Manual lists loss of appetite and low activity among the signs of pneumonia, with secretions from the nose or eyes and trouble breathing.

The RSPCA says to give wet or powdered food only when a vet advises it, for example because of dental problems, and to remove all traces of it at least twice a day because it grows mould and bacteria. The MSD page on disease risks covers the other conditions a vet may look for.

Planning for Absences

The RSPCA says to arrange a responsible person to look after your hamster while you are on holiday, to keep the hamster in its familiar cage with its usual food, and to avoid transporting it unless absolutely necessary. The RSPCA also says to avoid sudden changes to the diet, and the MSD Veterinary Manual lists travel stress among the things that can bring on diarrhea in a young hamster. A trip is a poor time to try a new food.

Give the sitter the daily jobs the sources describe: check that the bottle works, spot clean wet or soiled bedding, wash the food and water bowls, and remove any uneaten food (PDSA and RSPCA). Tell them where your hamster keeps its stash, which signs on the list above mean a call to the vet, and the vet's number.

If a child usually feeds the hamster, an adult needs to take over while you are gone. Our guide to the best hamster breeds for kids covers what a child can do and what an adult has to do. If your hamster is a long-haired Syrian, the sitter will also need our long-haired Syrian hamster care guide, which lists the extra coat jobs.

Daily Checks and a Safe Home

A short check each day catches most of what matters here: the bottle works, the bowl and the stash have food, the droppings are dry, the hind-quarters are clean, and the hamster is moving about as usual. The MSD Veterinary Manual says a hamster needs a solid floor, deep bedding, and an enclosure at least 6 inches (15 centimeters) high, and 8 inches (20 centimeters) or more is better because it allows deeper bedding. Our guide to picking a hamster’s cage compares options. The MSD Veterinary Manual also says tubes and boxes with holes give a hamster places to explore, and our page on the the best hamster tubes has picks.

READ NEXT: Can Hamsters Eat Walnuts? Nutritional Insights for Pet Owners

Frequently Asked Questions

What is the longest a hamster can survive without food?

No veterinary source gives a number. The RSPCA says domestic hamsters do not have enough fat reserves to survive without food for prolonged periods. A hamster that eats less than usual should be seen by a vet.

How long can you leave a hamster alone?

No veterinary source gives a number of days. The RSPCA asks for a responsible person to look after a hamster while you are away, and the RSPCA and PDSA both describe daily checks of food, water, and the bottle. If nobody can check each day, ask someone who can.

Can a hamster survive without water?

The sources give no number of days. The RSPCA and the MSD Veterinary Manual both say fresh water must always be available, and the Louisiana VMA puts a hamster's daily water at about 8 to 10 milliliters per 100 grams of body weight.

How long can a lost hamster survive?

The sources give no number. The MSD Veterinary Manual says hamsters are very good at escaping and can be hard to find once loose, and that they crawl into small hidden spaces such as under appliances and inside vents. Dogs and cats can also hurt a loose hamster. Cold is a risk too, since the RSPCA and PDSA both warn about torpor in a cold hamster. Start your search in those hidden spaces.

How long can dwarf hamsters go without food?

The sources give no separate number for dwarf hamsters. The same rules apply: food and water every day, and a call to the vet if the hamster eats less than usual.

How often should a hamster's cage be cleaned?

Clean your hamster's cage by changing the bedding at least once a week, a veterinary clinic's care guide says, and remove visibly soiled bedding every day. PDSA says small cages typically need a full clean once a week, while larger set-ups may only need it every few weeks.

Still need more info on hamsters? Check out everything you need to know about dwarf hamster sand baths!

Sources

• RSPCA, Creating a Good Home for Hamsters
• RSPCA, What to Feed Hamsters
• RSPCA, Hamster Health and Welfare
• PDSA, Hamsters as Pets
• MSD Veterinary Manual, Providing a Home for a Hamster
• MSD Veterinary Manual, Disorders and Diseases of Hamsters
• Louisiana Veterinary Medical Association, Biology of the Hamster
• Forever Vets, Keeping Your Hamster and Its Cage Clean