What’s the difference between an antiviral and an antibiotic?

Ask the Pharmacist

What’s the difference between an antiviral and an antibiotic?

Simply put, antivirals kill viruses, and antibiotics kill bacteria. Both of these medicines are called antimicrobials.

There are many more types of antibiotics than antivirals. Bacteria are relatively simple in terms of their makeup and construction, so it’s easier to develop drugs to target them.

On the other hand, antivirals are difficult to develop. Viruses are tricky. They change frequently, so even when you think you’ve got a handle on a virus, it can mutate and turn into a cousin of its original self.

While drug resistance is a problem with both of these antimicrobials, viruses can become resistant quickly, while bacteria resistance can sometimes take years.

Probably the best-known antiviral right now is Tamiflu, which targets flu viruses. It’s most effective when given within 48 hours of the onset of symptoms, and it decreases the duration of symptoms by about 1.25 days.

ABOUT TODAY'S EXPERT:

Sniffle Solutions expert Paul L. Doering, who holds a master’s degree in science, is a distinguished service professor of pharmacy practice at the University of Florida’s College of Pharmacy in Gainesville.