Gram Stain

A Gram stain is a type of test that helps tell whether bacteria causing an infection are Gram-positive or Gram-negative. This can help a doctor choose the best treatment for an infection.

The Gram stain is done by putting a special dye on the bacterial cells. Gram-positive bacteria retain the dye and turn a different colour than Gram-negative bacteria do. Sometimes more testing is done after the Gram stain to identify the specific kind of bacteria and the antibiotics that can kill them.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

Thanks to our partners and endorsers: