1. Decreased Appetite -- It is extremely important to monitor your pet’s appetite closely. In fact, even if your pets appetite begins to increase that could be a sign that something is wrong (E.g. Cushings disease in dogs and Hyperthyroidism in cats are two examples). A decreased appetite is one of the most common symptoms that a veterinarian will encounter and is also a symptom that is seen in a variety of medical conditions. A decreased appetite could be a result of pain, abdominal discomfort and even cancer to name a few. Most importantly, your pet is trying to tell you something and the sooner that your vet can evaluate the better.
2. Increased Thirst -- Especially important for cats. Three of the most common conditions that affect cats are Diabetes Mellitus, Renal Insufficiency (Previously known as Chronic Renal Failure) and Hyperthyroidism (over-active thyroid gland). All three of these conditions share a common symptom -- Polydipsia (Increased thirst) and Polyuria (Increased urination). All of these diseases are very manageable but early detection and diagnosis is critical. If you notice your cat drinking more water, go to your vet ASAP.
3. Hiding/Decreased Interaction with Family Members -- Dogs and cats desire to survive is based on their instinct. In the wild, if an animal is injured or sick, it will often remove itself from others and its environment to hide and seek shelter. This is a protective mechanism to help ensure survival as wounded or sick animals in plain sight of predators do not fend well. In the domestic setting, if you notice that your pet is lying or hiding underneath furniture or going down in the basement when it usually would not, that is a sign that something potentially serious is affecting your pet.
4. Red and Squinting Eye(s) -- A red, squinting eye often indicates significant discomfort to the eye. Glaucoma for instance is an ocular condition in which the pressure within the eye ball increases. If left untreated, even for a few hours, permanent blindness may ensue. The first few symptoms of Glaucoma often include a red eye, squinting and decreased appetite and prompt treatment is extremely necessary. Another common condition that can result in a red, squinting eye is a Corneal Ulcer. Corneal ulcers are extremely painful and if left untreated, may result in permanent damage to the affected eye.
5. Painful and/or Trouble Urinating -- Extremely important for male dogs and cats but in any case, if your notice your pet straining to urinate and nothing, or a small dribble is being produced, seek veterinary attention immediately. Dogs and cats at any age can have bladder stones and crystals without any symptoms. Should a small stone or collection of crystals create an obstruction, your pet will have a great deal of difficulty urinating and a life threatening condition will ensue. If left untreated, death may occur in as little as 36 hours.