Morphling first appeared when vials from Mrs. Undersee's supply were delivered at her request by her daughter Madge to Mrs. Everdeen to help treat Gale Hawthorne, who had been severely whipped by Romulus Thread.
In District 13, when Peeta would get angry, the doctors used morphling to sedate him.
Johanna Mason developed a minor addiction to morphling when she was hospitalized in District 13 for the torture she had received in the Capitol. She began to experience withdrawal when her supply was cut and started to tap into Katniss Everdeen's IV. However, she was so determined to directly participate in the rebellion on the front lines that she put up with the symptoms to continue her training.
Following Katniss' imprisonment for the murder of President Alma Coin, she considered overdosing on morphling tablets to commit suicide, but when she began to sing and found it hard to stop, she decided not to follow through. She also developed an addiction to the drug but was weaned off it.
- ↑ Catching Fire, Chapter 8