This information is for people who have pneumonia. It tells you about antibiotics, a treatment used for pneumonia. It is based on the best and most up-to-date research.
Do they work?
Yes. If you are very ill with pneumonia, taking antibiotics as soon as possible after you've been diagnosed improves your chances of making a full recovery. Antibiotics also make it less likely that you will die from pneumonia. But we don't know for certain which antibiotics work best.
What are they?
Antibiotics are drugs that kill bacteria, which are the germs that cause most cases of pneumonia. There are many different types of antibiotics. Some of the most common are listed below (with their brand names).
Cefuroxime (Zinacef, Zinnat)
Erythromycin (Erymax, Erythrocin)
Some of the newer antibiotics are called broad-spectrum antibiotics. They work against many of the different kinds of bacteria that can cause pneumonia. You're more likely to be given one of these antibiotics if you are very ill and you need to be treated quickly, even though doctors may not yet know which germ is causing your pneumonia.
To learn more, see Antibiotics used to treat pneumonia.
Antibiotics come as tablets and as a drip (sometimes called an intravenous infusion or IV). Most people can take them as tablets.  But if you can't take tablets for some reason (for example, if you feel ill and are vomiting) you will probably be given an antibiotic as a drip.How does your doctor choose an antibiotic?
In choosing an antibiotic, your doctor will take into account how severe your condition is, your age, your general health, what other illnesses you have, and what could be causing your pneumonia. Your doctor will also consider whether bacteria in the area where you live are known to be resistant to particular antibiotics. Resistance happens when germs change so that they are no longer destroyed by drugs that used to be able to kill them.
Your doctor will also want to know whether you've taken an antibiotic within the last three months. If you have, your doctor will probably prescribe a different type. This is because using the same antibiotic again can make bacteria resistant to it. 
If you are very ill with pneumonia, your doctor may give you an antibiotic that works against a lot of different germs. This may be a newer antibiotic. If you are not as ill, your doctor may prefer to stick with older drugs. This helps save the newer drugs so that doctors can use them when resistance has developed to the older ones.
To learn more, see Resistance to antibiotics.What if I have to go to hospital?