is the body’s internal response to infection, inflammation, immune disease, or other illnesses.

How to Check for Fever at Home (Step-by-Step)

You can’t reliably judge fever by feeling a pet’s nose or ears. The most accurate way is with a digital rectal thermometer.

1. Gather supplies: Digital thermometer (preferably one marked for pet use), water-based lubricant or petroleum jelly, treats, helper if available, and disinfectant/alcohol wipes.
2. Prepare your pet: Choose a calm area. Have someone gently hold your pet. Lift the tail carefully.
3. Lubricate and insert: Lubricate the tip and insert 1–1.5 inches into a dog’s rectum (0.5–1 inch for most cats and small dogs). Be gentle—do not force.
4. Wait for the beep: Hold the thermometer steady until it beeps. Remove and read.
5. Record and clean: Note the reading, time, and your pet’s behavior. Clean the thermometer thoroughly.

Ear and forehead/infrared thermometers can be less accurate in pets and may miss fever. If your pet won’t allow a rectal temperature and you’re concerned, contact your vet.

Pet Fever Symptoms and Other Warning Signs of Sick Pets

Fever often appears with other symptoms that point to the cause. Below are common problems, what they may mean, and what to do next.

Fever and Lethargy

What you may see: Tiredness, hiding, reluctance to play or walk, warm ears or belly, shivering, or body aches.

Possible causes: Viral or bacterial infections, tick-borne disease, abscesses (e.g., after a bite), immune-mediated illness, post-vaccine response, or inflammatory disorders.

What to do: Check a rectal temperature. Encourage rest, keep water available, and monitor breathing and gum color.

When to take your pet to the vet: Temp ≥103.0°F (39.4°C), any fever in a puppy/kitten or senior pet, fever lasting more than 24 hours, or if your pet is extremely sluggish, painful, not drinking, or breathing fast.

Loss of Appetite and Weight Loss

What you may see: Skipping meals, eating less than usual, weight loss over weeks, or sudden pickiness.

Weight loss in pets—common causes:

• Dental pain, oral ulcers, or broken teeth
• Parasites in pets symptoms: worms, Giardia, coccidia (often with diarrhea)
• Chronic GI disease, food intolerance, or malabsorption (e.g., exocrine pancreatic insufficiency in dogs)
• Kidney disease, liver disease, diabetes (dogs and cats), hyperthyroidism (common in older cats)
• Chronic infections, cancer, or immune-mediated disease

What to do: Offer fresh water; try warmed, smelly food (like warmed canned food) for 24 hours if no vomiting/diarrhea; never force-feed if choking risk. Track exact intake.

When to take your pet to the vet: Not eating for 24 hours (cats even sooner), weight loss over a few weeks, or poor appetite with vomiting, fever, or behavior changes. Cats that stop eating are at risk for hepatic lipidosis—seek care promptly.

Vomiting and Diarrhea

What you may see: One-time upset vs repeated episodes, blood in stool or vomit, foreign material, fever, or lethargy.

Possible causes: Dietary indiscretion, parasites, infections, pancreatitis, toxin exposure, foreign body obstruction, or sudden diet changes.

What to do: Withhold food for 6–8 hours (not water) if a single mild episode in an adult pet; then feed a bland diet (boiled chicken and rice, or vet-recommended GI diet) for 24–48 hours. Collect a stool sample for your vet if diarrhea persists.

When to take your pet to the vet: Repeated vomiting, blood, foreign object suspicion, severe pain, bloat signs (distended abdomen, unproductive retching in dogs), or any vomiting/diarrhea with fever, dehydration, or weakness.

Drinking and Urinating Changes

What you may see: Thirsty more or less than usual, frequent urination, accidents, straining, blood in urine, or vocalizing in the litter box.

Urinary problems in pets—key concerns:

• Male cats straining but not producing urine: Medical emergency due to potential urinary blockage. Seek immediate care.
• Frequent small urinations, strong odor, blood, licking the genital area: Possible UTI or bladder inflammation.
• Markedly increased thirst and urination: Could suggest kidney disease, diabetes, Cushing’s (dogs), or hyperthyroidism (cats).

What to do: Provide fresh water, monitor urine output, and note any accidents or blood. Do not delay if your male cat cannot pass urine.

When to take your pet to the vet: Any suspected blockage, blood in urine, painful urination, fever with urinary signs, or sudden changes in drinking or urination.

Coughing, Sneezing, Nasal or Eye Discharge

What you may see: Sneezing, cough, nasal discharge (clear, yellow, or green), runny eyes, squinting, fever, or decreased energy.

Respiratory infection in pets: Dogs may develop kennel cough or pneumonia; cats commonly get upper respiratory infections (herpesvirus, calicivirus). Some infections are contagious to other pets.

What to do: Isolate sick pets from housemates if contagious illness is suspected, keep them warm and hydrated, use a humidifier in the room, and gently wipe discharge. If breathing is labored (belly effort, flaring nostrils, blue or gray gums), seek emergency care.

When to take your pet to the vet: Coughing more than a day, breathing difficulties, fever, loss of appetite, lethargy, or green/yellow nasal discharge.

Skin, Ears, and Parasites

Ear infection symptoms in pets: Head shaking, scratching, foul odor, redness, discharge, or head tilt. Pain when touching the ears is common.

What to do: Do not use cotton swabs deep in the ear. Avoid homemade solutions that may irritate. A vet exam can identify yeast, bacteria, or mites and prescribe the correct treatment. Clean only with vet-approved solutions as directed.

Parasites in pets symptoms: Flea dirt (black specks), scratching, hair loss, pale gums (anemia), visible ticks, “rice-like” tapeworm segments near the anus, roundworms in stool/vomit, scooting, pot-belly in kittens/puppies, or chronic soft stool.

What to do: Use veterinarian-recommended flea/tick and deworming preventives year-round. Bring a fresh stool sample to the vet for testing if diarrhea or weight loss persists.

Pain, Lameness, and Neurologic Signs

What you may see: Limping, reluctance to jump, crying when touched, stiffness, seizures, disorientation, or collapse.

Possible causes: Injury, arthritis, infection, tick-borne disease, spinal problems, toxin exposure, or metabolic disease.

When to take your pet to the vet: Any collapse, seizures, acute pain, inability to use a limb, or neurologic changes—seek prompt veterinary care.

Dehydration Signs in Pets: How to Check

• Gums: Tacky or dry gums indicate dehydration; healthy gums are moist.
• Skin tent: Gently lift skin over the shoulders. If it stays tented more than 1–2 seconds, dehydration may be present. Note: This test is less reliable in thin, elderly, or very elastic-skinned pets.
• Eyes: Sunken eyes can signal significant dehydration.
• Behavior: Lethargy, weakness, and refusal to eat often accompany dehydrated states.

When to seek help: Any dehydration with vomiting/diarrhea, fever, or if your pet won’t drink. Kittens, puppies, and seniors dehydrate quickly—err on the side of caution.

When to Take Your Pet to the Vet

Use these thresholds to decide when to seek professional care:

• Temperature of 103.0°F (39.4°C) or higher, or any fever in a very young, elderly, or immunocompromised pet
• Temperature of 105.0°F (40.6°C) or higher at any time—urgent care needed
• Not eating for 24 hours (or any anorexia in cats), repeated vomiting/diarrhea, or signs of dehydration
• Breathing difficulty, open-mouth breathing in cats, persistent coughing, or blue/gray gums
• Male cat straining to urinate with little to no output—emergency
• Severe pain, collapse, seizures, or sudden profound lethargy
• Known toxin exposure, foreign-object ingestion, or rapidly worsening symptoms

If you’re unsure, call your veterinary clinic or an emergency hospital—describe your pet’s symptoms and temperature for tailored advice on when to come in.

First Aid and Home Care While You Wait

• Cooling for fever: For high fever (but not heatstroke), place cool, damp cloths on paw pads, ears, and belly. Use a fan. Do not use ice baths.
• Hydration: Offer fresh, cool water. Consider low-sodium broth or ice chips if safe. Do not force water into a vomiting or choking pet.
• Bland diet: If advised by your vet for GI upset, try small, frequent meals of a bland diet for 24–48 hours.
• Separate sick pets: Isolate from other household animals if a contagious respiratory or GI illness is suspected.
• Never give human medications: Do not give ibuprofen or naproxen to dogs; never give acetaminophen to cats; avoid aspirin unless your vet directs a specific dose. Many human meds are toxic to pets.
• Monitor and log: Record temperature every 4–6 hours, appetite, water intake, urination/defecation, energy, and breathing rate.

Common Causes Behind Fever and Illness in Pets

• Infections: Bacterial (abscesses, UTIs, pneumonia), viral (parvovirus, distemper in dogs; herpesvirus, calicivirus in cats), fungal, or protozoal (Giardia, coccidia)
• Parasites: Fleas, ticks, mites, intestinal worms—can cause anemia, GI signs, and secondary infections
• Tick-borne diseases: Lyme, Ehrlichia, Anaplasma—fever, lameness, lethargy
• Immune-mediated disease: The body attacks its own cells, leading to fever and other systemic signs
• Inflammatory conditions: Pancreatitis, severe dental disease, ear infections, or skin infections
• Neoplasia (cancer): Can cause fever, weight loss, and lethargy
• Heatstroke/hyperthermia: Environmental overheating rather than fever; requires immediate cooling and vet care
• Post-vaccination fever: Mild fever and lethargy can occur within 24–48 hours; persistent or severe signs warrant a call to the vet

Prevention: Reduce the Risk of Fever and Illness

• Vaccination: Keep core vaccines current (e.g., distemper-parvo for dogs, FVRCP for cats); discuss lifestyle-based vaccines with your vet.
• Parasite prevention: Year-round flea, tick, and heartworm preventives; routine deworming as recommended.
• Nutrition and water: Feed a balanced diet appropriate for life stage; ensure constant access to clean water.
• Dental care: Regular brushing and professional cleanings reduce pain, infection, and appetite loss.
• Grooming and skin checks: Inspect ears, skin, and coat weekly for redness, odor, fleas/ticks, or sores.
• Weight and activity: Keep pets at an ideal body condition; weigh monthly to catch early weight loss or gain.
• Heat safety: Avoid exertion in hot weather; never leave pets in vehicles; provide shade and water.
• Minimize stress and exposure: Quarantine new pets; avoid crowded or poorly ventilated environments if respiratory outbreaks are reported.
• Regular vet checkups: Annual or biannual exams, especially for seniors, help catch subtle problems early.

Build a Simple Home Health Log

Tracking normal baselines makes it easier to spot early changes. Keep a notebook or app with:

• Resting temperature, heart rate, and breathing rate when your pet is healthy
• Weekly weight and body condition notes
• Daily appetite, thirst, urine and stool quality/frequency
• Medications, preventives, and vaccine dates
• Any new behaviors or exposures (travel, boarding, new foods, encounters with wildlife)

Consider a small home kit: digital rectal thermometer, lubricant, alcohol wipes, vet-approved ear cleaner, bandage materials, a soft muzzle (for dogs), and your veterinarian’s and nearest emergency hospital’s contact information.

Problem–Solution Quick Guide

• Problem: Warm ears, lethargy, temp 103.4°F; mild appetite decrease. Solution: Offer water, rest, recheck temp in 4–6 hours; book vet visit if persists or worsens.
• Problem: Cat stopped eating and is hiding; sneezing with green discharge. Solution: Humidify air, gently clean discharge, call the vet today; cats should not go 24 hours without eating.
• Problem: Dog straining to urinate with visible blood. Solution: Seek prompt veterinary exam—possible UTI or stones; collect a urine sample if you can.
• Problem: Male cat in litter box repeatedly, crying, little to no urine. Solution: Emergency immediately—possible urinary blockage.
• Problem: Dog with sudden high fever (105.2°F), rapid breathing. Solution: Begin gentle cooling of paws/ears, do not use ice, go to emergency vet now.
• Problem: Kitten with diarrhea and weight loss. Solution: Vet visit for fecal testing and deworming; maintain hydration.

FAQ

Can I tell if my pet has a fever by touching their nose?
No. A wet or dry nose is not a reliable indicator. Use a digital rectal thermometer for accuracy.

What can I give my pet to reduce a fever?
Do not give human fever reducers. Ibuprofen and naproxen are toxic to dogs; acetaminophen is extremely dangerous to cats. Only give medications prescribed by your veterinarian.

How long can I monitor a mild fever at home?
If your adult pet is otherwise bright and drinking, you may monitor up to 24 hours while tracking temperature every 4–6 hours. Seek care sooner if the fever reaches 105.0°F, your pet worsens, stops drinking, or shows other concerning signs. For puppies, kittens, seniors, or chronically ill pets, call your vet right away.

Can vaccines cause a fever?
Mild fever and lethargy may occur within 24–48 hours after vaccination. If the fever is high, lasts longer than two days, or your pet has facial swelling, hives, vomiting, collapse, or trouble breathing, seek veterinary care immediately.

My pet won’t allow a rectal temperature—what now?
Do not risk being bitten or injuring your pet. Call your vet; they may recommend coming in, using a different thermometer, or offering a gentle sedative in select cases.

Is panting normal in cats?
No. Cats rarely pant. Open-mouth breathing or panting in a cat is an emergency and needs immediate veterinary attention.

Important Caution

If your pet shows severe symptoms, is very young or elderly, has a temperature of 105.0°F (40.6°C) or higher, is struggling to breathe, or cannot urinate, contact a veterinarian or emergency clinic immediately. When in doubt, call your vet—timely care can be lifesaving.