Medications Used to Stimulate Appetite in Dogs & Cats

When a dog or cat stops eating, it's often a cause for concern. A decreased appetite, medically termed anorexia or hyporexia, can signal an underlying health issue. While addressing the root cause is critical, sometimes a veterinarian may recommend medications to stimulate appetite in dogs or cats. These appetite enhancers for dogs and cats aim to encourage eating while diagnostic tests are run or while the pet recovers from an illness or treatment.

Understanding Appetite Loss in Pets

Before discussing specific medications, it's important to understand why a pet might lose its appetite. It's rarely just about being "picky." A diminished desire to eat can stem from a wide array of factors, from mild, temporary issues to serious, chronic diseases.

Common causes of appetite loss include:

• Pain: Dental pain, orthopedic pain, or abdominal pain can make eating uncomfortable.
• Nausea and Vomiting: Gastrointestinal upset is a frequent culprit.
• Stress and Anxiety: Changes in environment, new pets, or separation anxiety can affect eating habits.
• Systemic Illnesses: Kidney disease, liver disease, cancer, infections, and endocrine disorders often lead to a general feeling of unwellness that reduces appetite.
• Medication Side Effects: Some drugs can cause nausea or taste changes.
• Age-Related Changes: Older pets might experience a diminished sense of smell or taste, or have underlying health conditions.
• Environmental Factors: Unpleasant food smells, dirty bowls, or an uncomfortable eating location.

A veterinarian will typically conduct a thorough examination, including blood tests, urinalysis, and possibly imaging, to pinpoint the reason behind the appetite reduction. Only once the underlying cause is being addressed, or if it cannot be immediately identified, will appetite stimulants be considered as a supportive measure.

Appetite Stimulants for Dogs and Cats: An Overview

Appetite stimulants are not a cure for the underlying problem causing appetite loss. Instead, they are tools to help bridge the gap, encouraging a pet to eat enough to maintain energy and nutrient intake while the primary health issue is being managed. This can be crucial for recovery, as prolonged lack of food can lead to muscle wasting, nutrient deficiencies, and a weakened immune system.

The choice of medication depends on several factors: the pet's overall health, potential underlying conditions, possible drug interactions, and the veterinarian's experience.

Common Medications Used to Stimulate Appetite

Several medications are used off-label or specifically approved to help increase dog appetite and feline appetite.

Mirtazapine

Mirtazapine is an antidepressant in humans but acts as a potent appetite stimulant and anti-emetic (anti-nausea) in dogs and cats. It works by blocking certain serotonin receptors in the brain, which affects both appetite and nausea centers.

• Mechanism: Primarily acts as a 5-HT3 receptor antagonist, which reduces nausea, and also has effects on histamine and alpha-2 adrenergic receptors, leading to increased appetite.
• Formulation: Available as oral tablets and a transdermal ointment (Mirataz®) specifically approved for cats. The transdermal option is often preferred for cats who are difficult to pill.
• Advantages: Dual action (appetite stimulation and anti-nausea), effective in many cases, especially for cats.
• Considerations:
  • Side Effects: Can include vocalization, agitation, increased heart rate, drowsiness (especially in dogs), and serotonin syndrome if combined with certain other medications.
  • Dosage: Dosing varies between species and is typically administered every 24-48 hours.
  • Contraindications: Should be used with caution in pets with liver or kidney disease, and those on other serotonergic drugs.

Capromorelin (Entyce® for Dogs, Elura® for Cats)

Capromorelin is a ghrelin receptor agonist. Ghrelin is often called the "hunger hormone" because it plays a key role in regulating appetite, body weight, and growth hormone secretion. By mimicking ghrelin, capromorelin directly stimulates hunger.

• Mechanism: Binds to and activates ghrelin receptors in the hypothalamus, the part of the brain that controls hunger.
• Formulation: Available as an oral liquid, specifically approved for appetite stimulation in dogs (Entyce®) and cats (Elura®).
• Advantages: Directly targets hunger pathways, generally well-tolerated, and has specific veterinary approval.
• Considerations:
  • Side Effects: Can include increased salivation, vomiting, diarrhea, and lethargy.
  • Dosage: Administered once daily.
  • Contraindications: Use with caution in pets with kidney or liver disease.

Cyproheptadine

Cyproheptadine is an antihistamine with additional serotonin-antagonist properties. While it's primarily known for its anti-allergy effects, its serotonin-blocking action in the hypothalamus can lead to increased appetite, particularly in cats.

• Mechanism: Acts as a serotonin antagonist, which can indirectly stimulate appetite. It also has antihistaminic and anticholinergic effects.
• Formulation: Oral tablets.
• Advantages: Inexpensive, readily available.
• Considerations:
  • Side Effects: Can cause sedation, dry mouth, and excitement (paradoxical effect) in some cats.
  • Effectiveness: Generally considered less potent as an appetite stimulant compared to mirtazapine or capromorelin, especially in dogs. More commonly used in cats.
  • Dosage: Typically administered orally once or twice daily.

B vitamins (e.g., Cobalamin/B12)

While not direct appetite stimulants in the same way as the medications above, B vitamins, particularly cobalamin (Vitamin B12), help significantly in metabolism and nerve function. Deficiencies can lead to poor appetite and energy levels.

• Mechanism: B vitamins are cofactors for many metabolic processes. Cobalamin is vital for red blood cell formation and neurological function. Deficiency can cause lethargy and anorexia.
• Formulation: Injections (often subcutaneous), oral supplements.
• Advantages: Generally safe, essential for overall health, and can be very beneficial if a deficiency is present.
• Considerations:
  • Not a direct stimulant: Will only improve appetite if a deficiency is contributing to the problem.
  • Diagnosis: A blood test can determine if a B12 deficiency exists.
  • Side Effects: Few side effects associated with appropriate supplementation.

Prednisone/Prednisolone

Corticosteroids like prednisone are potent anti-inflammatory and immunosuppressive drugs. A well-known side effect of these medications is increased appetite and thirst. While sometimes used to stimulate appetite, this is typically a secondary benefit when the drug is prescribed for another condition.

• Mechanism: Affects multiple metabolic pathways, leading to increased hunger.
• Formulation: Oral tablets, injections.
• Advantages: Can be very effective at increasing appetite.
• Considerations:
  • Significant Side Effects: Long-term or high-dose use carries substantial risks, including increased thirst and urination, muscle wasting, panting, susceptibility to infection, and adrenal suppression.
  • Not a primary appetite stimulant: Rarely prescribed solely for appetite stimulation due to potential side effects unless there's an underlying inflammatory condition that also benefits from steroid treatment.
  • Withdrawal: Requires careful tapering when discontinuing.

Comparing Appetite Stimulants

Here's a comparison of the primary appetite stimulants discussed:

Medication	Primary Mechanism	Common Use (Species)	Key Advantages	Main Considerations
Mirtazapine	Serotonin receptor antagonist (anti-nausea, appetite)	Cats, Dogs	Dual action (anti-nausea + appetite), transdermal option for cats	Sedation, agitation, caution with liver/kidney disease
Capromorelin	Ghrelin receptor agonist (direct hunger signal)	Dogs, Cats	Direct hunger stimulation, veterinary approved	Vomiting, diarrhea, increased salivation, newer and more costly
Cyproheptadine	Serotonin antagonist, antihistamine	Cats (less so dogs)	Inexpensive, readily available	Less potent, sedation, excitement (paradoxical effect in cats)
B Vitamins	Metabolic cofactors	Dogs, Cats	Safe, addresses deficiency	Only effective if deficiency present, not a direct stimulant
Prednisone	Corticosteroid (anti-inflammatory, appetite side effect)	Dogs, Cats	Potent appetite increase	Significant side effects, not for sole appetite stimulation

Beyond Medication: Tips to Improve a Dog's Appetite (and Cats)

While medications can be vital, they are often part of a broader strategy to help a pet eat. Here are some non-pharmacological tips to improve a dog's appetite and how to improve a dog's appetite:

1. Address the Underlying Cause: This is always the first and most important step. Treating pain, nausea, or disease will naturally improve appetite.
2. Offer Palatable Foods:
   • Warm Food: Gently warming wet food (to body temperature, not hot) can enhance its aroma and make it more appealing.
   • Stronger Smells: Dogs and cats rely heavily on smell. Offering foods with a stronger, appealing aroma can entice them.
   • Variety (Carefully): While consistency is often good, sometimes a novel flavor or texture can spark interest. However, sudden changes can also cause digestive upset.
   • "Human" Foods (Vet Approved): Small amounts of plain, cooked chicken, boiled hamburger, or low-sodium broth can be very enticing. Always check with your vet before offering human foods. Avoid anything with onions, garlic, grapes, or xylitol.
3. Small, Frequent Meals: Instead of two large meals, offer several small meals throughout the day. This can be less overwhelming and easier to digest.
4. Create a Calm Eating Environment: Ensure the eating area is quiet, clean, and free from distractions or competition from other pets.
5. Hand-Feeding: Some pets, especially those who are weak or anxious, may respond better to being hand-fed.
6. Elevated Bowls: For pets with neck or back pain, an elevated food bowl might make eating more comfortable.
7. Hydration: Ensure constant access to fresh water. Dehydration can worsen appetite.
8. Patience and Persistence: It can take time for an appetite to return to normal. Avoid forcing food, which can create a negative association.
9. Consider a Feeding Tube: In severe or prolonged cases of anorexia, especially when the gastrointestinal tract is functional, a temporary feeding tube might be necessary to provide essential nutrition and allow the pet to recover strength. This is a veterinary procedure.

When to Seek Veterinary Attention

Any sudden or prolonged loss of appetite in a dog or cat warrants a visit to the veterinarian. While an occasional skipped meal might not be critical, consistent refusal to eat for more than 24 hours (especially in cats, where liver problems can develop quickly) or a significant decrease in food intake over several days is a cause for concern.

Other warning signs that accompany appetite loss include:

• Vomiting or diarrhea
• Lethargy or weakness
• Weight loss
• Changes in drinking habits
• Pain or discomfort
• Changes in behavior

Early intervention can significantly improve outcomes for pets experiencing appetite loss.

Related Reading

• Allergy and Itch Relief Medications for Dogs and Cats
• 18 Essential Minerals for Dogs and Cats
• 20 Natural Home Remedies for Cats and Dogs
• All Pet Health & Wellness Products For Dogs & Cats

Conclusion

A healthy appetite is a cornerstone of a pet's well-being. When a pet stops eating, it's a signal that something is amiss. While the primary focus should always be on diagnosing and treating the underlying cause, veterinary-prescribed appetite stimulants can serve as a good tool to help sustain a pet's nutritional needs during recovery. Coupled with supportive care and a comfortable environment, these medications can significantly aid in a pet's journey back to health. Always consult with your veterinarian to determine the best course of action for your pet's specific situation.

FAQ

Is there something to stimulate a dog's appetite?

Yes, several medications are available to stimulate a dog's appetite, including prescription drugs like mirtazapine (off-label for dogs) and capromorelin (Entyce®), as well as supportive therapies like B vitamin injections. Your veterinarian can determine the most appropriate option based on your dog's health condition.

What is the 7 7 7 rule for dogs?

The "7-7-7 rule" is not a recognized veterinary guideline or rule related to appetite stimulation. It is sometimes mentioned in internet discussions, often informally referring to various arbitrary timeframes or observations. For a dog's health, particularly appetite, it's best to rely on established veterinary advice rather than informal rules. If your dog isn't eating, consult a veterinarian promptly.

What to do when a dog has no appetite?

If your dog has no appetite, the first step is to contact your veterinarian. They will need to perform an examination and possibly diagnostic tests to identify and treat the underlying cause. In the meantime, you can try offering small amounts of highly palatable, warmed food, ensure a quiet eating environment, and make sure fresh water is readily available. Do not force-feed your dog without veterinary guidance.