She grew up in New Ulm, Minnesota and graduated from high school in 1977.
Eyrich went to St. Cloud State for three years, then graduated from Minnesota State.
Eyrich has worked on numerous film and telivision productions created, written, and produced by Glee co-creator Ryan Murphy. Such as his directorial debut Running with Scissors, and the FX black- comedy Nip/Tuck. She recently finished working on another Ryan Murphy show. The anthological series American Horror Story: Asylum.
In 2010 and 2011, she was nominated for a Primetime Emmy in the Outstanding Costumes for a Series category for her work on Glee. She was also awarded in 2010, 2011 and 2012 by the Costume Designers Guilde for best costumes in the Outstanding Contemporary Television Series, including a Career Achievement award. Her work on American Horror Story: Asylum received an award from the Costume Designers Guild in the Outstanding Made for TV Movie or Mini Series category.
- Alexander McQueen is one of Eyrich's favorite designers.
- During the shooting of the American Horror Story Pilot, Lou was diagnosed with breast cancer. So she was not able to work on the show until it's second season.
- For the costume design for Glee, Eyrich liked to use vintage finds from the stores Decades, American Rag, The Way We Wore, and Resurrection.