Anti-Inflammatory Drugs

29.1.3 Anti-Inflammatory Drugs Inflammation is the body’s response to microbial, chemical or physical injury. Inflammation causes heat (fever), redness, pain, swelling, and loss of function. A good example of this process is a bee sting. In most cases inflammation is the body’s way of fighting the attack, controlling damage and beginning the process of repair. In some cases the inflammatory process can become a long-term problem. In these cases it may be helpful to decrease the inflammation by giving anti-inflammatory drugs. These drugs come in two large groups “steroids” and “non-steroids.” “Steroids” resemble hormones made in the body like cortisone that normally limit inflammation. “Non-steroids” are synthetic drugs like aspirin that block the signs of inflammation. Each group has its own set of good and bad effects. “Steroids” decrease the body’s defense against infectious disease and produce excessive appetite, weight gain, water consumption and urination. “Non-steroids” can irritate, and cause ulcers in the gastrointestinal system. The following list of anti-inflammatory drugs includes those that are most commonly available for use in animals.

Steroids Warning:

1. Steroids should not be given to pregnant animals unless it is necessary to save the mother’s life. If they are given, especially in the last few months of pregnancy, the baby will most likely be aborted (die and be born early) 2-4 days after the injection is given.

2. If the animal has a wound, it must never be given steroids without an antibiotic injection at the same time, or the animal may die from an infection.

DEXAMETHASONE

Indications: Dexamethasone is a potent and long lasting steroid anti-inflammatory. It is useful in the treatment of arthritis, lameness, and muscular injuries.

Dosage and Route:

Horses- 0.02-0.2 mg/kg by mouth, IM, IV, daily Cattle- 5-10 mg/kg IM, IV, daily Swine- 1-10 mg IM, IV, daily Dogs- 0.25-1.25 mg by mouth, daily for 3-5 days; or Cats- 0.125-0.5 by mouth, IM, IV, daily for 3-5 days Rabbit- 2.6-4 mg/kg IM, as needed Withdrawal Period: Unknown Precautions: See warning above.

PREDNISOLONE

Indications: Prednisolone is a medium duration steroid that is useful in the treatment of arthritis, lameness, and muscular injuries. It is almost identical to prednisone.

Dosage and Route:

Horses- 0.25-1.0 mg/kg IM daily Cattle- 0.2-1.0 mg/kg IM daily Swine- 0.2-1.0 mg/kg IM daily Dogs- 0.5 mg/kg by mouth, every 1-2 days Cats- 1.2 mg/kg by mouth, every 1-2 days Withdrawal Period: Unknown Precautions: See warning above.

Non-Steroids ASPIRIN – See Oral medicines, 29.2.5 in this chapter.

FLUNIXIN MEGLUMINE (Banamine, Finadyne)

Indications: Flunixin meglumine is a very potent (aspirin-like) anti-inflammatory which is used primarily in horses and cattle to treat lameness, colic, and calf scours (diarrhea).

Dosage and Route:

Horses- 1.1 mg/kg by mouth, IM, IV, 1-3 times daily Cattle- 2.2 mg/kg IV every 12 hours if needed for a total of 3 doses Swine- 2.2 mg/kg by deep IM injection every 12 hours if needed for a total of 3 doses (according to Australian Package insert)

Llama- 0.5-1 mg/kg IV 1-2 times daily Dogs- 0.5-1.0 mg/kg IV only once or twice.

Withdrawal Period: Cattle- meat 14 days, milk 4 days Warning: Do not use in cats. Use with caution in pregnant animals. High doses for prolonged periods will cause gastrointestinal ulcers. The drug relieves pain so well that it has also been accused of masking the severity of colic and therefore delaying more effective treatment like surgery. Do not use in combination with any one anti-inflammatory drugs.

PHENYLBUTAZONE (Bute, Butazolidin) See Oral Medicines in this chapter, 29.2.5.