Visualizing fentanyl’s potency

Imagine this square represents one power unit of morphine.

M

Heroin is about twice as strong as morphine.

H
=
M

Fentanyl is up to 50 times stronger than heroin, and about 100 times stronger than morphine.

F
=
H
=
M

Fentanyl can kill at 2 milligrams, depending on a person's body size, tolerance and past usage. The national Drug Enforcement Agency has found counterfeit pills ranging from 0.02 to 5.1 milligrams of fentanyl per tablet.

Lethal doses of Fentanyl relative to a pencil and penny:

A lethal dose of fentanyl on the tip of a pencil to emphasize the smallness of the amount. A lethal dose of fentanyl next to a penny to emphasize the smallness of the amount.

Source: DEA