Hedgehog Health Problems: What to Watch For and When It's Time to Call a Vet

Hedgehogs are quiet, nocturnal, and very good at keeping their problems to themselves. That's not a charming quirk — it's a survival instinct that makes them genuinely difficult patients. By the time a hedgehog is visibly unwell to the average owner, the underlying condition has often been building for days or weeks. Many hedgehog health problems share the same early signs: reduced activity, not eating, staying curled longer than usual. Without knowing what to look for, it's easy to miss the window when intervention makes the most difference.

We see this regularly. An owner brings in their hedgehog because it seems "off" — a little slow, not finishing meals. On examination, we find significant weight loss, dental disease that's been progressing for months, or a mass that's become large enough to affect eating. Hedgehogs don't announce when something is wrong. You have to know what normal looks like so that abnormal registers early.

This guide covers the most common hedgehog health problems, which ones are emergencies, and what husbandry details prevent the majority of them. We also cover when to come in rather than waiting to see what happens — because with hedgehogs, waiting is usually the wrong call.

The Most Common Hedgehog Health Problems

Wobbly Hedgehog Syndrome (WHS)

Wobbly Hedgehog Syndrome is a progressive neurological disease found exclusively in African pygmy hedgehogs, and it's one of the most serious diagnoses we see in this species. The disease causes muscle wasting that typically begins in the hind legs, causing the hedgehog to wobble or drag its back end when walking. Over time, the weakness progresses forward — eventually involving the front legs and trunk as well.

Most hedgehogs with WHS begin showing symptoms between two and three years of age. The onset can be gradual enough that owners initially chalk up the wobbling to normal aging or clumsiness. There is no cure, and no treatment has been shown to halt the disease's progression. Management is supportive: adapting the enclosure to reduce fall hazards as mobility declines, ensuring easy access to food and water, monitoring body weight closely, and keeping the animal warm and comfortable. Some hedgehogs remain stable at early stages for extended periods; others decline more rapidly.

A genetic component to WHS is suspected based on breeding patterns, though the specific genetics have not been fully established. If your hedgehog came from a line where WHS has appeared, that history is worth sharing with your vet.

Hibernation Attempt

This is an emergency that many hedgehog owners don't know to watch for. African pygmy hedgehogs are not true hibernators. They did not evolve in environments where hibernation is a normal survival strategy. When the ambient temperature in their enclosure drops below approximately 65°F, their physiology responds as if they should hibernate — but they lack the physiological adaptations to do so safely. The result is a state of torpor that can become life-threatening within hours.

A hedgehog in a hibernation attempt will be cold and unresponsive, won't uncurl when handled, and may be breathing very slowly or barely perceptibly. It may feel completely limp rather than having the normal muscle tone of a curled hedgehog. Many owners find this in the morning after a cold night and assume the worst, but the animal may still be alive and recoverable if you act quickly.

Prevention is straightforward: keep the hedgehog's enclosure at 72–80°F at all times. This is non-negotiable. A digital thermometer inside the enclosure — not just a reading of the room temperature — is the only reliable way to confirm this.

Obesity and Fatty Liver Disease

Obesity is one of the most common hedgehog health problems we see, and it's almost always the result of two things: too many calorie-dense treats and too little exercise. In the wild, hedgehogs run one to three miles per night foraging. A hedgehog in an enclosure without a wheel, or with restricted activity, has nowhere to put those calories.

The practical test for a healthy body condition is simple: a healthy hedgehog should be able to curl into a complete, tight ball. When a hedgehog is overweight, there's too much fat to tuck away — the animal curls incompletely, with skin and fat visible around the edges. If your hedgehog can no longer fully curl, that's a problem.

Chronic obesity in hedgehogs leads to fatty liver disease (hepatic lipidosis), which can become serious quickly. Signs include lethargy, decreased appetite, and weight loss — ironically, an obese hedgehog that stops eating may lose weight rapidly and develop liver disease in the process. Mealworms are the most common culprit: they're high in fat, hedgehogs love them, and owners tend to give too many. They should be an occasional treat, not a diet staple.

The fix is a quality hedgehog kibble with an appropriate fat-to-protein ratio, strict limits on treats, and a solid-surface exercise wheel with a minimum diameter of 10–12 inches running every night. Wire wheels should be avoided — they catch legs and cause injuries.

Dental Disease

Periodontal disease is underdiagnosed in hedgehogs because the signs are easy to miss or misattribute. Over age three, we see dental disease frequently. The hedgehog's small size and tendency to curl makes oral examination at home nearly impossible — which means many cases go undetected until the animal is struggling to eat.

Signs to watch for include drooling or excessive moisture around the mouth, difficulty chewing or dropping food while eating, facial swelling (especially on one side), pawing at the mouth, persistent bad breath that seems worse than usual, and eventually reduced food intake as eating becomes painful. A hedgehog that used to finish meals and now seems disinterested in food warrants a dental check, not just a diet change.

Treatment requires a veterinary dental cleaning under anesthesia. Many hedgehogs also need dental radiographs to evaluate tooth roots and bone loss that isn't visible on the surface. Anesthesia carries higher risk in small exotic mammals, but untreated dental disease causes significant pain and can lead to systemic infection. We discuss anesthetic risk with owners before any procedure so you can make an informed decision.

Cancer (Neoplasia)

This is a difficult but necessary topic for hedgehog owners. Cancer is unfortunately very common in African pygmy hedgehogs, and the prevalence increases significantly after age three. Some estimates suggest that cancer is among the leading causes of death in this species. Knowing this doesn't make it easier, but it does make regular monitoring worth the effort.

The most frequently seen cancer in hedgehogs is oral squamous cell carcinoma — a tumor of the mouth and jaw. Signs include facial swelling, difficulty eating, drooling, and visible masses in or around the mouth. It can look very similar to dental disease in early stages, which is one reason oral exams under sedation are sometimes necessary to distinguish the two.

Female hedgehogs are also prone to mammary tumors. These present as lumps along the underside that you can sometimes feel when the hedgehog uncurls. Uterine tumors occur as well and may cause vaginal discharge or a distended abdomen. Internal tumors — involving the liver, spleen, or other organs — are harder to detect without imaging.

Annual exams allow us to palpate for masses and track any changes over time. A mass found early may be operable. A mass found late, when the animal has already lost significant weight and stopped eating, has far fewer options. The earlier the detection, the more we can do.

Mites and Skin or Quill Problems

Quill loss is normal in young hedgehogs during a period called "quilling" — similar in concept to teething, when juvenile quills are replaced by adult quills. This typically happens between six and eight weeks of age and again around four to six months. During these normal periods, quill loss is expected and the skin underneath should look healthy.

Adult quill loss is not normal. If a hedgehog over one year of age is losing quills in significant numbers, the most common culprit is mites — Caparinia tripilis, a species that infests hedgehogs specifically. Signs include excessive quill loss, dry or flaky skin (sometimes described as looking like dandruff on the quills and skin), intense scratching, and in heavier infestations, skin thickening and crustiness, particularly around the ears.

Diagnosis is made by a skin scrape — a simple in-clinic procedure. Treatment is antiparasitic medication, typically administered topically. The environment also needs to be treated, since mites can persist in bedding. Do not use over-the-counter flea or tick products on hedgehogs; many of the ingredients found in common pet store treatments are toxic to this species.

Respiratory Infections

Upper respiratory infections in hedgehogs are usually bacterial and can progress quickly. The signs are recognizable: nasal discharge (clear initially, becoming yellow or green with bacterial infection), sneezing, labored or audible breathing, lethargy, and loss of appetite. A hedgehog that is mouth-breathing is already in significant respiratory distress.

Respiratory infections often develop secondary to stress, drafty or cold enclosures, or following contact with a sick animal. They don't resolve on their own. Antibiotic treatment is required, and the appropriate antibiotic depends on culture and sensitivity when possible. Supportive care — maintaining warmth, ensuring hydration, and sometimes syringe-feeding if the animal has stopped eating — is part of management as well.

If you notice nasal discharge or labored breathing, don't wait to see if it improves. Hedgehogs are small animals with a fast respiratory rate, and infections that seem mild can become pneumonia within days.

Eye Problems

Hedgehogs have poor eyesight and rely primarily on smell and hearing to navigate. This means they run into things — cage walls, toys, food dishes — and corneal ulcers are a real consequence. Signs include a cloudy or hazy appearance to the eye, excessive blinking or squinting, and pawing at the affected eye. Corneal ulcers require veterinary treatment; they don't heal well without intervention and can progress to deeper corneal damage.

A bulging or sunken eye can indicate systemic illness, infection behind the eye, or a retrobulbar mass. Any sudden change in the appearance of the eye — including a significant change in size or prominence — warrants prompt evaluation. Proptosis, where an eye partially or fully protrudes from the socket, is an emergency requiring immediate veterinary care.

Husbandry: Getting the Basics Right

The majority of hedgehog health problems we see have a husbandry component — either a direct cause or a contributing factor. These are the non-negotiables:

• Temperature: 72–80°F at all times, measured inside the enclosure. This is the single most important environmental factor. A temperature below 65°F triggers hibernation attempt. A temperature consistently below 72°F stresses the immune system and predisposes to respiratory infections.
• Exercise wheel: Solid surface only — no wire or mesh that can catch legs and cause fractures or degloving injuries. Minimum 10–12 inches in diameter so the hedgehog runs with a neutral or flat back rather than arching. This is not optional enrichment; it's a health necessity. Hedgehogs need to run one to three miles per night.
• Diet: A quality hedgehog kibble with moderate fat and high protein. Insects (mealworms, crickets) are appropriate treats in small quantities — not daily staples. No grapes, raisins, or avocado. Fresh water always available.
• Cage size and enrichment: Hedgehogs are active and need space to move. Enrichment — hides, tunnels, foraging opportunities — reduces stereotypic behavior and stress-related illness.
• Annual vet exams: Starting at one year of age. Over age three, twice-yearly is reasonable. Hedgehogs hide illness well enough that an annual physical is often the only way to catch problems before they become advanced.

When to See a Vet Urgently

Some situations with hedgehogs cannot wait. These warrant a same-day call rather than a "let's see how it does overnight" approach:

• Cold, unresponsive, won't uncurl — hibernation attempt, treat as an emergency
• Any wobbling, hind leg weakness, or dragging of the back end
• Not eating for 24 hours or more — hedgehogs have a high metabolic rate and cannot safely fast for long
• Labored, audible, or open-mouth breathing
• Swelling around the face, jaw, or mouth
• Sudden severe quill loss in an adult hedgehog
• Any eye that is bulging, sunken, or has rapidly changed in appearance
• Visible mass or lump on the body that wasn't there before

If you're not sure whether something is urgent, call. A quick conversation is far better than discovering too late that a two-day delay mattered. Hedgehogs are small animals with limited physiological reserve — they can decline faster than larger pets, and they don't show distress in ways that make the urgency obvious.

We see hedgehogs and other exotic small mammals at South Pasadena Animal Hospital, located in Alhambra and serving the greater San Gabriel Valley. To schedule an appointment, call (626) 441-1314 or book online. Appointments are required — we do not accept walk-ins.

Frequently Asked Questions About Hedgehog Health