5 Causes Excessive Drooling in Rabbits

Sloppy, ropey strands of drool dripping from your rabbit’s mouth – it’s an alarming sight for any bunny owner. While a little salivation is normal for rabbits, excessive drooling can signal serious health issues. From dental problems to heat stroke, what causes rabbits to drool too much? How do you know if your rabbit is drooling excessively? What diagnostics and treatments will the vet recommend? This article dives into the 5 most common reasons for abnormal rabbit drooling. We’ll explore the symptoms, vet workup, latest therapies, and prognoses, so you can get your bunny the best care. Read on to learn what’s behind copious rabbit drool and how to nip the problem in the bud.

What Are the Causes of Excessive Salivation in Rabbits?

Excessive drooling, also known as ptyalism or sialorrhea, is characterized by an overproduction of saliva that leaks out of the mouth. While some drooling is normal in rabbits, especially when anticipating food or getting ready to groom themselves, excessive drooling can indicate an underlying health issue. Here are 5 of the most common causes of excessive drooling in rabbits:

Dental Concerns

Dental issues are one of the most frequent causes of ptyalism in rabbits. Like humans, rabbits have two sets of teeth that are constantly growing. The teeth can overgrow or misalign, causing pain and difficulty eating. Specific dental problems that can lead to excessive drooling include:

Malocclusion: This is when the upper and lower teeth don't align properly. Food gets trapped between the misaligned teeth, leading to overgrown teeth that press painfully on the gums.
Molar spurs: Spurs are sharp points that develop on the cheek-side (buccal side) of the molars. They dig into the gums and cheeks.
Abscesses: Abscesses are pockets of infection at the roots of the teeth. They are very painful and make it hard to chew.
Fractured teeth: Cracks or fractures in the teeth expose the sensitive inner pulp and make eating excruciating.

With dental discomfort, rabbits excessively salivate as their body tries to lubricate the mouth and flush out food debris. The drooling tends to worsen during and after meals. Your rabbit may show signs of dental disease like reduced appetite and weight loss.

Heatstroke

Sustained heat stress, also known as heatstroke, can lead to heavy drooling along with other signs like lethargy, panting, and red or blue ear tips. Unlike dogs, rabbits don't effectively control their body temperature by sweating. So in hot weather, they struggle to release excess heat.

Heatstroke occurs when a rabbit's body temperature rises to dangerous levels above 103°F (39°C). As the body tries desperately to cool off, blood flow increases to the salivary glands. This ramps up saliva production. The dripping saliva helps to dissipate some warmth.

Other cooling mechanisms like widened blood vessels and panting also kick in. These efforts help prevent organ damage, brain injury, and even death from occurring. But they often aren't enough. Temperature keeps climbing. At this point, emergency cooling with chilled IV fluids, ice packs, and damp towels is necessary.

Medical Conditions

Several medical conditions can increase drooling due to inflammation, obstruction, or damage involving the salivary glands. These include:

Sialoceles: These are large, fluid-filled cysts that form on the major salivary glands under the jaw (submandibular gland). They compress the glands, causing painful swelling and excessive saliva flow. The condition often arises from an injury to the jaw area.
Salivary mucoceles: These mucus-containing cysts develop when a salivary gland duct gets blocked. The dammed up saliva spills out into surrounding tissues. Saliva production is disrupted, leading to ptyalism.
Salivary gland infection: Bacterial infection of any salivary gland will cause it to swell and drool excessively. Dental problems often precede salivary infections.
Tumors: Both cancerous and benign tumors on the salivary glands can increase salivation. The sheer bulk of the tumor causes congestion and back up of saliva.
Nerve damage: Injury to the nerves that stimulate saliva production can throw off normal signals to the salivary glands and cause oversecretion of saliva. Common causes are bites, blows to the head, and sometimes, stroke.
Foreign bodies: Small sticks, grass awns, or burrs stuck in the back of the mouth can overstimulate saliva production as the body tries to move the object forward. Excess drooling is the result.
Oral medication: Certain drugs like morphine, barbiturates, and toxic plants can affect the nerves controlling saliva output. Side effects may include drooling.

What Are the Signs of Excessive Drooling in Rabbits?

How do you know if your rabbit is drooling excessively versus normally? Here are some red flags:

Pendulous strands of saliva hanging from the mouth
Wetness around the mouth, chin, and front paws from drool
Damp, smelly patches on the neck and chest
Skin irritation, redness, or fur loss around the mouth from constant wetness
Drooling during times when rabbits normally don't, like when resting
Upswing in water consumption to counteract fluid loss from increased drooling
Appetite changes, chewing difficulties, weight issues indicative of dental or mouth pain
Head shaking, teeth grinding, or pawing at the face suggesting oral discomfort
Plaintive vocalizations when eating due to sore mouth
Drooling along with signs of illness like lethargy, weakness, breathing issues
Inability to retain food or water in the mouth due to excessive outflow of drool
Dehydration signs like sluggishness, dry skin, reduced urination if drooling is profuse

If your rabbit displays any of these symptoms, schedule a veterinary exam right away. The sooner the underlying issue is identified and treated, the sooner the extreme drooling will resolve.

Diagnosis

To get to the root cause of abnormal drooling in rabbits, veterinarians will perform a detailed oral exam plus diagnostic testing. Here are components of the diagnostic workup:

Medical history – The veterinarian will ask about the drooling onset, duration, any associated symptoms, and potential incidents that could have sparked it. Details about diet, housing, behavior changes, and recent introductions of new foods, treats, or chew toys are also pertinent.
Physical exam – The vet will check the rabbit's vitals, hydration status, body condition, and look for any swelling, trauma, or skin irritation around the head and mouth. Palpating for injuries or abnormal masses in the jawline, neck, and skull may provide clues.
Oral exam – This involves lifting the lips to inspect the front incisors for overgrowth, misalignment, fractures, resorption, or other problems. The vet also examines the inside of the cheeks, gums, tongue, palate, back molars, and throat for pain, ulcers, masses, foreign material, or additional dental issues.
Skull and jaw X-rays – Radiographs allow vets to visualize the teeth roots for infection, the jawbone for fractures or cysts, and sinuses for obstructions causing drooling through the nose. They also show swallowed foreign objects.
Blood tests – Blood work helps detect infections, kidney issues, toxins, hormonal imbalances, or other systemic causes for increased drooling.
Salivary gland ultrasound – This imaging modality visualizes salivary glands and ducts to identify cysts, infections, or masses interfering with saliva flow.
Biopsies – The vet may collect small tissue samples from mouth lesions or enlarged salivary glands for laboratory analysis. This determines if cancer, infection, or another disorder is present.
Bacterial culture – Swabbing the mouth and culturing the bacteria on Petri dishes can identify a pathogenic infection requiring targeted medication.
Excretory sialography – Infusing dye into the salivary ducts makes blockages or anatomical defects visible on X-rays. The test pinpoints duct obstructions, strictures, cysts, or salivary gland damage.

The veterinarian may run other diagnostics like a CT scan if the initial testing is inconclusive about the drooling's underlying cause.

Treatment

The appropriate treatments for excessive rabbit drooling depends on the specific health problem identified through diagnostic testing. Here are some common treatments the veterinarian may recommend:

Dental disease

Tooth trimming/extraction – The vet clips or pulls damaged, overgrown, or infected teeth causing drooling and pain. This is often done under anesthesia.
Root canal therapy – Deep cleaning and disinfecting the hollow insides of fractured teeth can resolve dental infections and trauma.
Corrective filing – For misaligned bite, the veterinarian will file the overgrown teeth back to proper lengths and angles. Ongoing filing is needed to prevent recurrence.
Antibiotics – If gum or tooth root abscess are present, antibiotic injections or oral medication will be prescribed to eliminate the infection.
Pain medication – Anti-inflammatories and pain relievers make the rabbit more comfortable when eating with sore teeth.
Diet change – The vet may recommend softer foods, critical care formula, or grinding pellets while mouth pain subsides.

Salivary gland disorders

Salivary duct flush – Flushing obstructed ducts can help expel plugs of debris, inflammation, or strictures.
Sialocele drainage – Needle aspiration drains the fluid out of large salivary cysts compressing the glands.
Salivary gland removal – If severely damaged or cancerous, the affected gland may be surgically excised. This curbs overproductive drooling.
Medication – Antibiotics, anti-inflammatories, or drugs that reduce saliva production may be prescribed.

Foreign bodies

Sedation and retrieval – The rabbit is sedated so the veterinarian can sweep the mouth and throat to locate and extract the foreign item.
Esophagoscopy/endoscopy – Scoping the upper digestive tract helps find and grasp objects stuck farther down.

Nerve damage

Medication – Drugs that reduce saliva output may provide temporary relief while nerves regenerate.
Acupuncture – Fine needles placed in specific body points may help relieve drooling caused by nerve dysfunction.
Physical therapy – Exercises and massage can aid recovery from injury to nerves controlling salivary glands.

Overheating (heat stroke)

Cooling – Bringing the rabbit's temperature down with cool IV fluids, ice packs, wet towels, cage fans, and AC prevents organ damage.
Supportive care – Once stable, providing subcutaneous or IV fluids, nutrition support, blood work, and monitoring in the hospital may be needed.
Prevention – Ensuring adequate shade, cool housing, frozen water bottles, and diet adjustments can stop recurrences.

Following the veterinarian's treatment plan closely gives affected rabbits the best chance of recovering from excessive drooling and remaining comfortable.

Recovery

The prognosis for rabbits with excessive drooling depends greatly on the underlying cause. In general:

Dental disorders have a good prognosis when treated, though they may require lifelong management. Meticulous at-home dental care helps.
Salivary gland infections, obstructions, and trauma often resolve fully with appropriate treatment and minor surgery if needed.
Heat stroke recovery is variable – the longer the temperature stays critically high, the higher the risk for lasting organ damage or death. With prompt cooling, many rabbits survive.
Advanced dental disease, malignant salivary gland tumors, and severe nerve damage have more guarded prognoses.

To optimize recovery during treatment and convalescence:

Make sure the rabbit eats enough. Assist feeding if needed. Support gut health with probiotics.
Watch for signs of pain like tooth grinding. Give analgesics as directed.
Limit pellet portion sizes. Offer soaked hay and leafy greens to encourage chewing and dental wear.
Keep the mouth clean. Gently wipe drool and provide supervised access to clean water.
Watch for recurrence of drooling, which may signal an incompletely treated problem. Follow up as recommended.
Monitor weight and hydration status if drooling is still heavy. Give subcutaneous fluids if dehydrated.

With cooperative veterinary care and attentive nursing at home, most cases of excessive drooling can be successfully managed for good quality of life. Pay close attention to oral health going forward to prevent recurrence.