Drugs for Different Body System Disorders

Many heart drugs used in animals are the same as those used in people. Some work directly on the heart and blood vessels. They work in different ways to help the heart to pump better or to beat in a normal rhythm or the blood vessels to dilate more easily to improve blood flow. Drugs that work on blood itself can either increase blood cell production (such as when treating anemia), control bleeding, or prevent or decrease the risk of blood clot formation.

Digestive drugs can change how fast food moves through the gut, treat digestive tract infections, and treat ulcers or diarrhea. They can be used to stimulate the appetite, control or cause vomiting, decrease stomach acid, or help block signals from the brain that cause nausea. There are also drugs that protect the intestinal lining or help remove toxic substances, and others that slow or speed up intestinal movement.

Eye medications can be applied to the surface of the eye, injected around or into the eye, or even given by mouth or by injection into skin or muscles. In some cases, medications may be given by two different routes (such as by mouth and by eye drop) at the same time. The method chosen depends on which part of the eye needs treatment. There are eye drops that treat infections, decrease inflammation, and even lower the pressure inside the eye in cases of glaucoma.

A variety of drugs affect muscles and bones. These include muscle relaxants to decrease stiffness, anti-inflammatories to decrease inflammation, and even medications that can cause temporary muscle paralysis to keep animals still for surgery. In addition, nutrients and supplements may be given when deficiencies of particular nutrients in the diet cause muscle or bone problems.

Just as with people, drugs may be given to pets to treat problems with the nervous system. Three major categories of drugs are used in animals to treat brain, spinal cord, and nerve disorders:

• Anticonvulsants are used to control seizures.

• Tranquilizers and sedatives are used to decrease anxiety.

• Psychotropic agents, such as antianxiety drugs, antipsychotics, antidepressants, and mood stabilizers, are often used to treat anxiety, fear-related behaviors, compulsive disorders, and some aggression problems.

A variety of respiratory drugs are used to treat lung and airway disorders in animals:

• Cough suppressants lessen the cough reflex. Some are opioids (codeine, hydrocodone, butorphanol) that work well to suppress coughs but can have side effects.

• Bronchodilators relax the airway muscles so that air flows more easily, making it easier for pets to breathe. They can also decrease inflammation and clear mucus.

• Anti-inflammatory drugs decrease airway inflammation in cases of allergic bronchitis or asthma, but they can suppress the immune system and are not used to treat infections.

• Antibiotics and antifungals are used if a bacterial or fungal infection is present.

• Inhaled drugs are delivered at high levels directly to the lungs via nebulizers or inhalers.

• Expectorants break up mucus in airways, making the mucus easier to cough up and clear from airways.

• Decongestants are rarely used in animals, but they can be applied topically or given by mouth to decrease nasal congestion.

Skin problems often have several causes, so identifying and treating all factors gives the best chance of eliminating them. Treatment can be long-term and often aims at controlling the condition rather than curing it. Skin drugs include various medications and supplements:

• Antibiotics are used to treat bacterial skin infections. Veterinarians usually start by prescribing drugs that are effective against common skin bacteria before test results that identify specific bacteria are back.

• Antifungals treat fungal skin infections. The drug used and the means of administration depend on the fungus and the animal species being treated.

• Antiparasitics control parasites such as fleas, mites, and digestive system parasites.

• Antihistamines prevent itching and inflammation. Some of them cause drowsiness or digestive upset. They should be used exactly as prescribed, because overdoses can have dangerous consequences.

• Essential fatty acids should be part of your pet's diet to help keep the skin healthy. Additional fatty acids might be needed, beyond those that are taken in with food, to treat certain skin conditions in animals.

• Hormones such as steroids decrease inflammation and immune system responses, and they are used to treat many allergic and skin conditions caused by allergies and other responses by the immune system. Other hormones (thyroid hormone, sex hormones, melatonin) can treat conditions that cause hair loss.

• Immunomodulators stimulate or suppress the immune system. They are used to treat chronic infections or skin conditions caused by allergies or other responses by the immune system.

• Psychotropic agents are used to treat excessive licking or similar obsessive behaviors.

• Vitamins and minerals such as retinoids (vitamin A–like compounds) and zinc can help certain skin conditions. Animal breeds that can't absorb enough zinc need to be given zinc supplements throughout their lives to keep their skin healthy.

A variety of drugs are used to treat disorders of the urinary and reproductive tracts:

• Antibiotics are commonly used to treat bacterial infections of the urinary tract. Some antibiotics are more appropriate for treating urinary tract infections because they reach higher levels in the urine (versus the blood or the digestive tract) after they are taken. These antibiotics are usually prescribed when animals first develop signs of a urinary tract infection (such as more frequent urination or pain when urinating). Animals with urinary tract infections that keep coming back after treatment with antibiotics might need to have their urine tested to identify the specific bacteria causing the infection, along with the most effective antibiotic to use to kill those bacteria.

• Antifungals are used in rare instances when infection of the urinary tract is caused by a fungus.

• Drugs that control urine pH (the amount of acid in the urine) can help prevent the formation of certain types of urinary tract stones, such as kidney stones or bladder stones.

• Diuretics increase urination to remove excess water from the body in conditions like kidney or heart failure. These drugs increase thirst and urination, so it's important that your pet has access to water.

• Hormones for reproductive disorders are drugs derived from natural hormones that control or induce estrus (being in heat to breed), stimulate sperm production, or manage breeding.