Dear Doctor: Our young son fell off his skateboard recently, and the items my wife and I needed to tend to his cuts and scrapes were scattered throughout the house. Now we want to assemble a home first-aid kit. What should it contain?

Dear Reader: Great idea! A well-stocked first-aid kit is an important safety feature for every home. And while first-aid kits are available for purchase, you can easily put one together yourself.

Take an afternoon to evaluate your family needs, make a list, then hit your local drugstore. With just a little bit of planning, you'll be ready to handle the minor bumps and mishaps of everyday life at a moment's notice.

With a home first-aid kit, you're preparing to deal with three basic types of medical issues -- injury, infection and allergy.

Everyday injuries include scrapes, cuts, splinters, burns, sprains and stings. Infections may range from an inflamed wound to fever, a sore throat or the flu. You'll also want to be prepared for common allergic reactions such as the rash from poison oak and poison ivy, and itching and swelling from insect stings.

It's important that if anyone in your family has severe food allergies or a respiratory condition such as asthma, you stock a backup of the appropriate medication. Mark each item with its expiration date and replace as needed. It's a good idea to keep a separate checklist, which will make it easy to know when it's time to replace that inhaler or EpiPen.

So how do you build a first-aid kit?

Start with a container such as a plastic storage tub, a tackle box or a tote bag with separate compartments. It should be easy to open, easy to carry, and have enough room for everything to be organized and recognizable at a glance.

Delegate one compartment for personal items -- those allergy medications we talked about or backup doses of any other vital medications your family members may need. You'll also want to include a list of emergency phone numbers.

For a family of four to deal with common emergencies, you should have:

-- 2 absorbent compress dressings

-- 25 adhesive bandages of assorted sizes

-- 1 adhesive cloth tape

-- Antibiotic ointment and antiseptic wipes

-- Ibuprofen

-- Acetaminophen

-- An instant cold compress

-- Non-latex gloves to be worn when dealing with blood or bodily fluids

-- Hydrocortisone ointment

-- A pair of scissors and a set of tweezers

-- A 3-inch and a 4-inch roller bandage

-- 10 sterile gauze pads (3 by 3 inches and 4 by 4 inches)

-- An oral thermometer that is not glass and does not contain mercury

-- 2 triangular bandages

-- A good first-aid instruction booklet

Rather than in the bathroom, where humidity may affect the contents, keep your first-aid kit in the kitchen. It's also wise to consider a version of this kit for your car.

Finally, read through the first-aid instruction booklet on a regular basis. You don't want to be holding a page open while you're trying to bandage a sprained ankle!

(Eve Glazier, M.D., MBA, is an internist and assistant professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and primary care physician at UCLA Health.)

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095.)

Dear Doctor: If I received the flu shot in September, will I still be protected from the flu in March?

Dear Reader: That's a very good question -- and the answer depends, in part, on your current health.

The flu season normally lasts from November to March, but it can begin in October and even end in May. The injected influenza vaccine, which contains three to four inactivated viruses from the prior flu season, spurs the formation of antibodies to help your body fight off influenza if you're exposed. It takes about two weeks after the vaccine for your body to produce sufficient protective antibodies.

If you are a young, healthy person under 50, you're more likely to get a good immune response from the vaccine -- and also more likely to have an immune response that lasts six to 12 months. You'll also have a greater and longer-lasting immune response if you get the flu vaccine every year. So if you got your shot in September, you should have immunity that lasts throughout the flu season.

If you're older than 50 and have diabetes, cancer, or kidney or liver failure, your ability to mount a good response from the vaccine decreases. So six months after your vaccination, you may not have sufficient antibodies to ward off the flu. This has been shown specifically for the H1N1 influenza virus. If you received the vaccine on Sept. 1, you may be less protected by April of the following year against H1N1.

This decreased immunity is especially pronounced in people over the age of 65. It decreases even further among those over 65 who have chronic illnesses.

Some pharmacies have been administering the flu vaccine as early as the middle of August. This isn't necessarily a bad thing for someone older than 65 or someone with chronic illnesses, because you still get immunity from the vaccine that should last through much of the flu season. Still, it's probably better to wait until at least the middle of September to get the flu vaccine just to ensure you're protected for as much of the flu season as possible.

Finally, it's especially important to get yearly flu vaccines if you are: older than 60; between the ages of 6 months and 4 years; have chronic illnesses; or are pregnant. The flu is especially risky for these groups.

While imperfect, the flu vaccine is the best way our society has found to decrease the death rates and the long-term complications from a potentially fatal disease that causes anywhere from 3,300 to 49,000 deaths per year in the United States.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095.)

Dear Doctor: We live in a charming older home, but some of the paint looks old. How worried should I be that it might contain lead?

Dear Reader: You're right to be concerned about the possible presence of lead-based paint in your home. Even in small quantities, lead is toxic to humans and animals. Children under the age of 6 and pregnant women are particularly susceptible to the ill effects of lead.

Children who have ingested lead may suffer from hyperactivity, lowered IQ, anemia, impaired growth and hearing problems. In pregnant women, the presence of lead can slow the growth of the fetus, cause nerve or brain damage to the unborn child, and even lead to premature birth.

Long-term exposure to lead can cause serious physical and neurological problems in adults as well. High levels of the toxic metal are associated with damage to the kidneys, brain, bone marrow and blood, as well as fertility problems and nerve disorders.

If your home was built before 1978, the Environmental Protection Agency warns that yes, there's a strong chance it contains lead-based paint. Homes built after 1978, the year a federal ban on lead-based paints went into effect, are considered to be safe.

The probability of finding lead-based paint in your home increases along with its age. Homes built between 1960 and 1977 have a 24 percent chance of containing lead-based paint. That number spikes to 69 percent for homes built between 1940 and 1959. Homes that predate 1940 have a whopping 87 percent probability of containing lead-based paint.

So are you and your family at risk? Fortunately, even if you've found lead-based paint in your home, there's good news.

When it's intact and in good condition, lead-based paint is usually not harmful, according to the EPA. To remain safe, you should regularly check your home for deteriorating paint and immediately address any issues. You can go a step further and, by covering lead-based paint with new paint, drywall or wallpaper, you will stabilize it and protect it from damage.

Problems arise because as it ages, lead-based paint chips, cracks, peels and crumbles. The resulting particles mix easily with household dust and get distributed throughout the house.

Since kids tend to explore the world with their mouths, the chance that they'll ingest lead from older paint that is deteriorating is high. Sweeping, vacuuming or even a breeze from an open window can make lead-filled dust go airborne where your family and pets can inhale and absorb it.

To know whether or not the paint you are worried about contains lead, you can purchase a test kit at a hardware store or hire a certified inspector. If you plan to remove the paint or to do major renovations, it's important to use a certified contractor who will know proper abatement procedures.

Federal guidelines recommend that children who live in or regularly visit a home with lead-based paint be tested for lead levels in their blood. For children, this test is performed at 12 months of age. The health effects of lead are not reversible, so vigilance is your best protection.

(Eve Glazier, M.D., MBA, is an internist and assistant professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and primary care physician at UCLA Health.)

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095.)