Ask Dr. Weil by Andrew Weil : Fish oil is good for you and for cats 'n' dogs, too

A Fish oil is good for dogs — and cats! Veterinarians first used omega-3 fatty acids in the form of fish oil to treat canine allergies, but they now recommend it for a wide variety of conditions ranging from kidney disease to arthritis and high cholesterol. Adding fish oil to your dog's food provides anti-inflammatory effects and can help relieve itching due to atopic dermatitis, an allergy-related skin condition.

You can get fish oil supplements designed for pets from both Nordic Naturals and Animal Essentials (and, I'm sure, from other sources), but you also can use fish oil meant for humans, as long as you choose the correct dose. For example, Nordic Naturals recommends one capsule of its 1,500 mg soft-gel fish oil for dogs weighing 20 pounds or more. Smaller animals should get smaller doses. If you use fish oil that's intended for humans, you can give larger dogs a capsule or two (depending on the pill's dose), and puncture a capsule to squeeze some of the contents into the food of smaller dogs or cats.

By the way, to reduce my own risk of heart disease and cancer, I take 2 grams of fish oil a day and also eat fish — usually sockeye salmon — two or three times a week. I recommend that everyone eat two or three servings of fish per week, take a daily fish oil supplement, or consume another source of omega-3 fatty acids.

Before dosing your dog or cat with fish oil meant for humans or pets, I suggest consulting with your veterinarian, particularly in regard to dose. Pets with allergies may need higher than the standard doses, and they also may need supplemental GLA (gamma-linolenic acid), an omega-6 fatty acid that improves skin health. Your vet can best advise you about doses and whether or not a combination of the two would work better for your pooch than fish oil alone. You may not notice changes for at least six to eight weeks, so be patient.

My dogs don't have allergies or skin problems, but I add fish oil to their food at every meal for general health maintenance.

Complications of ringworm?

Q My 8-year-old son had ringworm on his head. It went away after using different medications, but now he has raised, dry and scaly bumps on his head, plus a few fever-blister-looking bumps on the back of his neck and lower eyelid. What causes this?

A Ringworm is a common infection caused by the tinea fungus that you can pick up from other people and from dogs and cats. The infection is called ringworm because of its appearance: a pinkish red rash that spreads in a circle (or ring) around a center of normal looking skin. The edge of the circle is raised and looks something like a worm under the skin.

Ringworm is typically treated with over-the-counter anti-fungal skin creams, powders or liquids, and it usually clears up in about four weeks. Although the infection generally doesn't cause serious problems, people with weakened immune systems may have some trouble getting rid of it. That might be the problem in your son's case.

I suggest that you take your son to his pediatrician for a diagnosis of the bumps on his head and the blisters on his neck and eyelid. If this is a stubborn case of ringworm, treatment with a prescription fungicidal cream or, if necessary, an oral anti-fungal agent should clear it up. If your son has developed a bacterial infection secondary to ringworm (from scratching), the pediatrician can prescribe an antibiotic.

I also recommend giving your son a multivitamin plus a supplement of GLA (gamma-linolenic acid) in the form of black currant oil or evening primrose oil. GLA often improves skin conditions. The correct dose for children is 250 mg twice a day.

In addition, you can use topical calendula cream or lotion made from petals of the ornamental "pot marigold" (Calendula officinalis) to soothe the affected areas of your son's skin. Look for products with at least 10 percent extract of this plant, and you might also try washing the irritated skin with a diluted solution of calendula tincture.