It’s a no-brainer that we don’t want our pets to suffer pain. Whether you ask a pet parent or a veterinarian, you’re likely to get an immediate answer that pain, when it is recognized, should be relieved. Unfortunately, once we start to dig even one layer beyond that simple sentiment, opinions begin to diverge on how to recognize pain in our pets and the best way to address it. This article is specific to dogs and cats, but many of the same principles also apply to horses, birds, and other companion animals.
All sentient beings feel pain. It is necessary to normal life. Pain tells us to rest an injured limb, to avoid hot stoves, to be careful with sharp objects. It can be said that innate fear of pain is at least as effective as pain itself—how often do you instinctively change a small behavior because you know that if you don’t, something will hurt? Our pets are the same, learning from infancy to avoid things that hurt, because pain signifies damage, and damage threatens life.
Likewise, the earliest medicine men/ shamans/healers sought ways to alleviate pain in their patients. They learned that willow bark contained a potent anti-inflammatory that later became aspirin, that poppies could be distilled into opium and its many derivatives; that applying cold or heat to an injury could affect swelling; and that stabilizing a broken bone greatly improved comfort and, consequently, healing.
Pain tells us to rest an injured limb, to avoid hot stoves, to be careful with sharp objects.
We are fortunate, indeed, to live in a time when we understand a great deal about how pain works, and therefore how best to treat it. Much is known, but more is being learned all the time. The causes and treatment options for pain are so numerous and varied that it goes far beyond the scope of this article to cover them all, so please check with your veterinarian if you are concerned your pet may be in pain.
Ways to Categorize Pain
1. Superficial vs. deep
Think about the difference between a skin wound or burn as opposed to a deep bruise, sprain or broken bone. Each travels a different nerve pathway to notify the brain there is a problem. Of course, one injury or condition may cause both types of pain.
Superficial pain is sharp and sudden. It sends impulses through a very short nerve “loop” that initially bypasses the brain altogether. You jerk your hand away from the hot stove before you feel the burn. It is usually managed where it lies, with bandages, topical medicine or local anesthesia. It’s rare for superficial pain to cause long-term problems, but if a nerve is injured or significant scar tissue forms, it can happen.
Deep pain uses nerve pathways that often trigger symptoms unrelated to the actual injury, such as nausea, fainting, and throbbing at the site of the injury. It may respond to ice or heat, but otherwise it’s hard to get at directly. Deep pain is far more likely to become chronic or maladaptive.
Management of deep pain may involve—
■ Medications such as NSAIDs, opiates, CBD, and others
■ Immobilization via bandages or surgery
■ Correction of the underlying problem, such as surgery to remove a tumor or alleviate an obstruction
This type of pain is a reason many pet owners cite when making the decision to seek euthanasia for a beloved pet.
2. Acute vs. chronic
Acute pain is sharp and attention-grabbing. It’s that “right now” impulse that demands you drop what you are doing and deal with it. Chronic pain is longer lasting—the nagging backache, for example. Because acute pain is often self-limiting, in most cases it does not require treatment. Chronic pain by definition is long-lasting.
3. Mild vs. severe
Pain scales for humans typically rate on a scale from one to ten, where one is mildly annoying and ten is completely debilitating. This is harder to gauge in pets, who often hide their symptoms and have wide-ranging tolerance. The urgency of treatment depends on the severity of the pain. In veterinary medicine, we tend to err on the side of wanting comfort so are more likely to treat than not. Because our patients can’t explain what they feel, we sometimes use treatment as a test. If the pet improves with pain relief, we assume it was in pain before treatment.
4. Visceral vs. orthopedic vs. nerve-generated
■ Orthopedic pain refers, of course, to bones, muscles, and joints—by far the leading cause of treatable pain in pets. Chronic orthopedic pain is the best understood type, and the pain with the most available therapies in veterinary medicine.
■ Visceral pain is also known as “referred” pain. Viscera—internal organs—don’t have nerves of their own, so when something goes wrong, they can’t send a direct impulse to the brain. Instead, they operate via “stretch” receptors, and the pain impulse may appear to come from a place other than the damaged organ. Think of a heart attack patient with shoulder pain, or the vague general ache associated with intestinal cramps. In veterinary medicine, this might be associated with a bleeding tumor on the spleen, or a blocked or displaced intestine. It may be the hardest for a pet owner to recognize, because the signs are vague.
■ Nerve pain is perhaps hardest of all to localize, because nerves travel from skin, muscle and bone through the spinal cord to the brain. Damage or irritation anywhere along that pathway can make it feel like that distant body part hurts, but the real problem lies in the spinal cord or even the brain. An example is sciatica.
5. Physiologic vs. maladaptive
■ Physiologic pain is just that—normal responsive pain that tells us something is wrong and that goes away when the problem is fixed. A broken bone that heals stops hurting.
■ Maladaptive pain involves ongoing pain that can literally feed on itself. For example, a chronically irritated nerve will trigger muscle cramps, which are, in turn, painful. In a syndrome called dorsal horn windup, nerve sensors at the edge of the spinal cord literally stimulate themselves, sending constant impulses to the brain telling it there is pain. But that pain can’t be alleviated by the natural responses—such as changing body position or stretching. Receptors in the brain become overstimulated and fire constantly. This is difficult pain to stop, because there are so many factors at work.
Therapeutic Options for Pain in Pets
1. Local therapy
Wounds are stitched, bandaged, salved or otherwise treated topically. Infections are addressed with antibiotics. The cause of the pain is obvious, and the treatment is directed at the immediate cause, often without the need for systemic therapy.
Depending on the nature and duration of the pain, this may include:
■ Anti-inflammatory drugs, such as NSAIDs (carprofen, Galliprant, and others). These go to the site of the injury and reduce inflammation that causes pain. They work within hours and may be used short or long term, or “as needed,” depending on the condition being treated.
■ Opiates, such as buprenorphine and Tramadol. These work on the pain receptors in the brain to reduce the sensation of pain. Strong opiates are rarely used in pets, except during and immediately after surgery or for acute severe pain, or unrelenting pain from chronic terminal conditions such as bone cancer. Tramadol, a weak opiate, is an exception. It is favored by many for being inexpensive and safe, but its benefits in pets are not proven. Besides, the tablets are large and taste awful, making it hard to administer in some case.
■ Supplements, such as glucosamine HCl, omega-3 fatty acids such as fish oil, Adequan (glycosaminoglycan) injections, and others. These are typically used over a longer period of time, and their effects are more subtle and prolonged. These are safe, often very effective, and readily available in affordable, over-the-counter formulas. Unfortunately, the supplement industry is poorly regulated, and many such products have little active ingredient when analyzed. Stick with name-brand products; when in doubt, check with your vet.
■ “Alternative modalities.” Beyond the scope of this article, this includes everything from CBD to acupuncture and cold laser therapy to stem cell therapy and many other therapies. While research is being done, scientific evidence is lacking for many such therapies. Nevertheless, most veterinarians feel that many of these treatments offer significant pain relief and should be considered on a case-by-case basis, especially when more traditional options either fail to work or cause unwanted side effects. It’s not really fair to lump all these modalities together, except that they share certain commonalities—we don’t have any way to measure the effects other than our subjective impressions that the pet is getting better. Some options—stem cell therapy for example—are quite expensive, invasive, and/or require ongoing visits to the vet. Others—CBD comes to mind—are surrounded by such fanaticism that it’s nearly impossible to have a rational discussion on the merits and drawbacks of their use.
Obviously, if the cause of the pain is a wound, single tumor or damaged organ, or a broken bone, then surgery to remove or repair the underlying problem is usually the best option. But even with severe arthritis, surgery to fuse the joint may provide long-lasting pain relief.
4. Radiation therapy
In cases where surgery isn’t appropriate, but pain—especially cancer pain—is severe, a series of radiation treatments may be recommended. The exact way this helps is complex and not fully understood, but check with your vet if other options have not worked.
Signs of Pain in Dogs
• Limping or difficulty walking/running/getting up/ climbing into car
• Decreased appetite, reluctance to chew or obvious care in chewing
• Panting or trembling while resting
• Increased aggressiveness or irritability
• Unusual sleep position, or restlessness/inability to get comfortable
• Change in expression—vacant look, staring, dilated pupils, squinting
• Whimpering or yelping when touched or moved
• Social withdrawal—less play, less interaction, less interest in attention
• Excess scratching, licking, pawing, head shaking or otherwise favoring one area
Signs of Pain in Cats
• Difficulty or reluctance jumping onto surfaces like beds and counters
• Appears clumsy or sometimes falls
• Decreased appetite, “just licks the gravy off the food”
• Seems withdrawn, is hiding more, less playful
• Change in expression—staring into space, dilated pupils, squinting
• Increased irritability or aggression, especially when touched or approached
• Restlessness or sleeping in unusual locations
• Biting, licking, scratching or rubbing excessively at one part of body
• Stops grooming, either completely or certain areas
Lillian Roberts, DVM, is the owner of Country Club Animal Clinic, which is located at 36869 Cook Street in Palm Desert. 760-776-7555 www.countryclubdvm.com