White blood cells are like having antibiotics during your chemotherapy treatment to fight infection. The doctor checks the number of white cells during your regular blood tests. If you need antibiotics you may be able to have tablets or capsules. But often, with chemotherapy related infections, you need to have antibiotics directly into the bloodstream. This treatment is often in most countries done in the hospital only by law.
In some circumstances, doctors prescribe antibiotics before you get an infection, to try to prevent this from happening. You may hear these called prophylactic antibiotics. 'Prophylactic' (pronounced prof-il-ak-tik) just means preventative. A clinical trial has recently looked into the usefulness of preventative antibiotics during chemotherapy. This was called the Significant trial.
Infections are often at a time when your white blood count may be low, it is essential that you contact your doctor as you may need urgent antibiotic therapy. Its always dangerous to have cases like this, its important to contact a doctor asap before the infection becomes more excessive and on certain cases, surgery would need to be involved if the right timing decisions arent made.