Examples

How It Works

Macrolides prevent bacteria from reproducing.

Why It Is Used

Doctors often use macrolides to treat pneumonia in otherwise healthy people younger than 65. For these people, macrolides are effective against the most common causes of bacterial infections in the lower respiratory tract.

Macrolides may be given to people who are allergic to penicillin.

Doctors use macrolides in people 65 and older and those with other long-lasting (chronic) health problems if the doctor suspects an uncommon cause of the pneumonia.

How Well It Works

In general, all antibiotics used have a high cure rate for pneumonia. For people in the hospital, cure rates are 73% to 96%. Outside of the hospital, cure rates are generally above 80%.¹

Macrolides are effective against a wide range of bacteria.

You most likely will have some improvement in symptoms 2 to 3 days after treatment begins. Unless you get worse during that time, treatment is not changed for at least 3 days. The number of days you continue to take antibiotics depends on your illness and the type of antibiotic.

Side Effects

The most common side effects of macrolides include:

• Diarrhea.
• Nausea.
• Upset stomach.
• Vomiting.
• Sore mouth.

A large study shows that people who take erythromycin along with certain common medicines may increase their risk of sudden cardiac death.² The study shows that the risk of sudden cardiac death is greater when erythromycin is taken with some medicines that inhibit certain liver enzymes-such as certain calcium channel blockers, certain antifungal medicines, medicines to stop vomiting, and some antidepressants-than when these medicines are not taken together.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Clarithromycin and azithromycin are more expensive than erythromycin, but both are effective against a wide range of bacteria and have fewer side effects. They may replace erythromycin when treating people who have pneumonia who also have other health problems or are 65 and older. Clarithromycin and azithromycin may be the best choice for people who:

• Cannot take erythromycin.
• Smoke.
• Are more likely to have pneumonia caused by Haemophilus influenzae.

All the macrolide antibiotics are effective against lower respiratory tract infections caused by Legionella pneumophila, which also causes Legionnaires' disease.

Long-acting antibiotics are usually given for a shorter length of time than standard antibiotics when treating bronchitis or pneumonia.

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Citations

1. Loeb M (2006). Community acquired pneumonia, search date April 2005. Online version of Clinical Evidence (15): 1–10.

2. Ray WA, et al. (2004). Oral erythromycin and the risk of sudden death from cardiac causes. New England Journal of Medicine, 351(11): 1089–1096.