 He appeared as a regular contributor to the Lifetime cable television show "Growing Up Together" from 1990 to 1992.In 2009, he became an assistant professor of pediatrics at the USC Keck School of Medicine.Karp is a founding board member of Healthy Child Healthy World, and has served on the advisory boards of the Green Guide, Babycenter.com, "Parents", "Ser Padres," and "American Baby" magazines.