I hope you're ready now to donate blood. To find a blood center near you, call the toll-free numbers listed here for the American Association of Blood Banks, America's Blood Centers or the American Red Cross. Or visit their Web sites.

Once your appointment is set, it's time to get ready. First, make sure you're eligible to donate. Although guidelines vary with each blood center, all follow certain mandated requirements.

To be eligible to donate blood, you must be in good health and at least 17 years old (although some states permit younger people, with parental consent, to donate). Few centers have any upper age limit. Generally, donors must weight at least 110 pounds and all must pass a physical and health history examination given prior to donation.

If you have experienced any of the following, you may find yourself "temporarily deferred." This means you can't give blood that day, but you can come back once the appropriate amount of time has passed or the situation has changed:
• Have had a heart attack in the last six to 12 months.
• Have had malaria in the last three years.
• Have visited areas where malaria is found in the last year.
• Have received blood, plasma or other types of blood components in the last year.
• Have been tattooed in the last year.
• Have had cardiac surgery in the last year or have not completely recuperated from the surgery and are taking cardiovascular medicine.
• Have been exposed to someone with hepatitis within the last year.
• Are not feeling well the day of the blood donation.
• Have taken antibiotics within the last 24 to 72 hours.
• Are pregnant or have had an abortion in the last six weeks.

If you meet any of the following criteria, however, you will be "permanently deferred." That means you can't donate blood. But you can still help. Ask your blood center about volunteer opportunities, or offer to organize a community or workplace blood drive.

People who have experienced any of the following may not donate blood:
• Have had hepatitis at age 11 or older.
• Are at high risk of contracting the HIV virus/AIDS.
• Have spent any cumulative period of three or more months in the United Kingdom from 1980 through 1996.

The day you're scheduled to donate, take these steps:
• Eat heartily and drink noncaffeinated, nonalcoholic fluids before you donate.
• Don't exercise immediately before you donate blood.
• Arrive on time.
• Bring a picture ID. You'll be asked to prove your identity.
• Relax during the donation, which only takes about 10 to 15 minutes.

What to Expect
When you arrive, you'll register and answer a series of questions concerning your medical history. Then, medical staff will conduct a health examination and measure your pulse, blood pressure, temperature and iron level. You may feel a little pain when the needle goes in, but some people don't feel any pain at all. It might help to look away while the needle is inserted. You'll lie down for about 10 to 15 minutes while a pint, or unit, of blood is collected.

After donating, you'll be asked to relax for a few minutes while you're served a light snack. While you're resting, ask the staff for a large glass (about 16 ounces) of water. Two studies presented at the 2002 American Heart Association's High Blood Pressure Conference found drinking water before and after giving blood can prevent fainting.

After Donating
After donating you should avoid muscle exercises, rough movements and weight lifting or picking up heavy objects for the first five hours after donation. Then mark your calendar: You can donate again in 56 days. If you donate every 56 days, you'll be able to donate six times a year. Over your lifetime, then (or until age 76) you could conceivably donate 48 gallons of blood!X