Determining whether your pet’s quality of life has diminished is an important step in the decision-making process.  There are four parts of your pets life to consider: Pain & suffering, eating & drinking, house soiling, and quality of life. 

How do I know if my pet is in pain or suffering?
    Unfortunately pets cannot tell us when they are in pain.  By nature, most pets are very good at hiding pain and suffering.   Common signs of pain are hiding, vocalizing, difficulty moving or getting comfortable laying down, restlessness, not sleeping well, excessive panting, not eating, relieving bowels inside the home or where the pet is laying down.  Some pets will protect an area that is painful and may even try to bite when touched.  Others may continuously lick at a wound or painful area.  If you believe your pet is painful and he/she is not currently under care for pain, please consult with your pet's regular veterinarian for an exam and pain management options.  In some cases, the pet is on pain medication that either is not effective or the pet is having undesired side effects from the medications.  Uncontrolled pain is an important reason to consider for euthanasia.  For more information about pet pain see the handout "how to tell if your dog is in pain" and "how to tell if your cat is in pain."

Is my pet eating and drinking?  Does he/she have uncontrollable vomiting and/or diarrhea?
   If your pet is unable to eat enough food or drink enough water, your pet maybe slowly wasting away and will become progressively weaker.  Ongoing uncontrolled vomiting and diarrhea lead to loss of fluids and nutrients.  Other medical conditions, such as cancer and kidney disease, can cause pets to be continually nauseous and can also rob pets of nutrients from food.  Refusing to eat/drink, ongoing weight loss, and uncontrolled vomiting/diarrhea are important considerations for euthanasia.

Is my pet urinating or defecating in the house or outside the litterbox? 
    Pets may urinate and defecate in the home or outside the litterbox for numerous reasons.  If pain, illness, or inability to get to the litterbox or to the door is causing house soiling, then this is an important quality of life issue for you and your pet.  Most pets are take great pride in using the appropriate location for urination and defecation.  Disease conditions or medications may cause the pet to drink more and produce more urine.  The pet may leak urine or not be able to make it through the night and have accidents.  In the most severe cases, the pets will defecate or urinate where they are laying and not be able to move away, this leads to skin infections and more serious medical conditions.

Is my pet happy?
    Every pet has special things he/she enjoys: a favorite toy, playing a game, meeting you at the door.  Can your pet enjoy these special things she/he used to?  When pets refuse to participate in what he/she used to enjoy and when pets separate from the family or do not want to be touched, this pet may be painful, suffering and/or have a serious underlying condition.  In general, if an owner truly believes that the pet is having more bad days than good days, it may be time to consider euthanasia.  If the last thought a pet owner has before bedtime is that they hope their pet passes in their sleep during the night, it may be time.

Additional considerations

Severe behavioral disorders
  Common behavioral disorders such as aggression or separation anxiety may pose a physical risk to family members, friends, other animals or the pet itself.  Some cases may be so severe that behavioral counseling and medical management is unable to help the pet be a safe addition to the home.  

Mobility
    As pets age, they may develop arthritis, neurological or other orthopedic diseases making it difficult for them to move around and get up from the floor.  They slip on slick surfaces and may fall in uncomfortable positions.  Large dogs may be too heavy for owners to be able to pick up and help outside so they can relieve themselves.

Respiratory difficulty
    Difficulty breathing is a strong indication that your pet is suffering.  Pets that are panting excessively at rest are having difficulty breathing.  Cat do not pant unless extremely stressed or due to serious (sometimes life-threatening) medical conditions.  Open mouth breathing or panting at rest are signs of severe respiratory difficulty are an important consideration for euthanasia.

Additional Resource for Quality of Life Assessment from Association of Pet Loss and Bereavement.