Tetanus shots: How often should I get boosters?

What happens if you get tetanus shots too close together? I was in the emergency room recently after stepping on a nail. I couldn't recall when I last had a tetanus shot, so the doctor gave me one. Later, I remembered that I had received a tetanus booster last year.

- Joseph / South Carolina

Answer

You did the right thing by getting a tetanus shot in that situation. Vaccination is the best way to protect against tetanus, a serious disease caused by a bacterial toxin that affects your nervous system. Adults should receive tetanus booster shots every 10 years. Although getting tetanus shots more frequently generally isn't harmful, it may increase the risk of soreness or redness at the injection site.

Tetanus bacteria can enter your body through even the tiniest cut or scratch. But deep puncture wounds — such as from stepping on a nail — are most susceptible to tetanus infection. If you suffer such an injury and it's been more than five years since your last booster, you should receive another tetanus shot. If you can't recall when you last received a tetanus shot, you should get the booster — especially if you're pretty sure it was more than five years ago.

Those who've never been immunized against tetanus should receive the initial tetanus series — three tetanus shots given over a period of seven to 10 months.