On page 41, Montag remembers the night that Mildred overdosed on sleeping capsules and she had to have her stomach pumped by the Electronic Eyed Snake.

What is the significance of Mildred overdose in Fahrenheit 451?

In Fahrenheit 451, the significance of the capsules that Mildred overdoes on is that it shows how fundamentally unhappy people are in this dystopia. The government wants everyone to be happy, which it aims to achieve by providing them with hours and hours of brainless entertainment on TV. But it's all just a sham.

Why does Mildred try to kill herself?

Mildred is the one major character in the book who seems to have no hope of resolving the conflicts within herself. Her suicide attempt suggests that she is in great pain and that her obsession with television is a means to avoid confronting her life.