Sometimes a combination of chemotherapy medicines is more effective than a single drug.

There is not a single drug that is a standard among treatment.

Every single drug that affects the body will have some side effects.

The antibiotics are either a single drug or a combination of drugs.

Another attraction is that a single successful drug will have the same relative importance to both companies.

All you had was a single effective drug and no vaccine?'

It often takes intensive medical study to gauge the effects, good and bad, of any single powerful drug.

"It's unlikely any single drug will be helpful for more than a fraction of the population."

Four years on, not a single patient has received a single drug.

"Almost every single illegal drug is down, and some dramatically."