When your pet’s eating and drinking habits change, you may wonder if they are simply being picky or they have a more serious condition. If you have not enticed your four-legged friend to eat or drink warmed canned food or water flavored with a bit of low-sodium broth in 24 hours, they need veterinary treatment. Conversely, your pet may suddenly develop a huge appetite or excessive thirst because of a multitude of health issues. Sudden changes in your pet’s eating and drinking habits can indicate a serious underlying problem, especially when your pet has other illness signs, like vomiting, diarrhea, or excessive urination.
While not all situations require emergency treatment, you should never let your pet’s abnormal behavior go on too long. We explain some of the most common conditions that cause appetite and thirst changes in pets that should not be ignored.
#1: Dental disease
Dental disease is one of the most common conditions that affects pets, with up to 90% of pets having some level of dental disease by age 3. However, pets may continue to eat and drink normally until their mouth becomes exceedingly painful, so identifying and treating dental disease in its earliest stages is important to prevent systemic infection and organ disease. The first dental disease signs you may notice include bad breath, plaque and tartar accumulation, and swollen, inflamed gums. As the disease progresses and infection increases, the teeth supporting structures weaken, resulting in loose or missing teeth, or tooth-root abscesses.
Any periodontal problem is painful for pets, yet they may not lose their appetite and thirst until their diseased teeth cause significant pain while they eat. Then, you may notice that your pet is chewing on one side of their mouth, dropping food while eating, licking the juice from canned food, or avoiding the food bowl altogether. Pets with a fractured tooth or tooth-root abscess are typically in acute pain, and these conditions require urgent treatment.
#2: Endocrine disorders
Endocrine disorders that affect your pet’s regulatory hormones can interfere with their eating and drinking habits. Common endocrine disorders in pets include diabetes, Cushing’s disease, hyperthyroidism, hypothyroidism, and Addison’s disease. These diseases can require emergency treatment as soon as your pet displays initial signs, especially if they compensated during the beginning disease stages and hid their illness until their condition progressed.
Each endocrine disorder can cause a significant change in your pet’s eating and drinking habits, or weight changes without corresponding appetite changes:
- Hyperthyroidism — Cats are much more likely to develop hyperthyroidism than dogs, and often lose weight, despite a voracious appetite. They can also drink and urinate more.
- Hypothyroidism — In general, dogs develop hypothyroidism more than cats, and their metabolism plummets. Despite an unchanging appetite, the dog often gains weight.
- Cushing’s disease — Pets with hyperadrenocorticism can develop an excessive thirst and hunger, and will urinate more frequently than normal.
- Addison’s disease — Vomiting, diarrhea, and anorexia are common with hypoadrenocorticism, which often causes dehydration.
- Diabetes — Uncontrolled diabetes generally causes increased thirst and hunger, and excessive urination.
Pets with endocrine disorders who have been previously well-controlled may relapse and require emergency stabilizing treatment.
#3: Organ dysfunction
Organ damage or disease that causes kidney or liver dysfunction can alter a pet’s eating and drinking habits. Acute organ injuries (e.g., toxicosis) or chronic conditions (e.g., chronic renal failure in cats) can also cause appetite and thirst changes that may suddenly develop. In general, pets with liver or kidney disease will experience anorexia, increased thirst, and increased urination.
#4: Gastrointestinal upset or blockage
An upset stomach can certainly make your pet feel so bad that they forgo eating and drinking, but some pets power through, although they may vomit or have diarrhea afterward. If your pet eats something that lodges in their gastrointestinal tract (e.g., a bone, string, or toy) they will not want to eat or drink. Surgical removal is required in these cases, and your pet’s appetite may not improve until several days after surgery.
Although owners commonly believe that cancer affects only older pets, a wide range of cancers can strike pets at any age. Changed eating and drinking habits may be subtle and non-specific, but often are the first indications of cancer. Pets with cancer often feel so poorly that they lose their appetite, and they may need to be encouraged to eat and drink. Certain cancers (e.g., lymphoma, osteosarcoma) are notorious for interfering with a pet’s appetite and thirst, but any cancer can trigger a decline in eating and drinking.
In many cases, pets can hide illness or disease until their condition advances and affects their eating and drinking habits. Some pets will continue to eat and drink normally until they are quite ill, which is often the case with dental disease. When in doubt that a sudden change in your pet’s appetite and thirst may be cause for concern, contact our Urgent Pet Care Omaha team for an appointment.