The products are the first generic treatments that compete directly with EpiPen, whose price has soared more than 400 percent in the past decade, and that can be used to replace the brand-name version.
"This approval means patients living with severe allergies who require constant access to life-saving epinephrine should have a lower-cost option, as well as another approved product to help product against drug shortages," FDA Commissioner Scott Gottlieb said in a news release.
The regulatory clearance comes as children prepare to return to school, a time when EpiPen sales typically jump as parents stockpile injectors.
The FDA in May added the EpiPen to its tally of drugs in short supply. Hundreds of patients across the country reported trouble getting prescriptions filled due to manufacturing issues at a Pfizer factory that makes the devices in partnership with Mylan.
The drug agency in 2016 declined to approve Teva's generic EpiPen, before its escalating cost hit the news.
Mylan had a $1 billion in brand-name EpiPen sales that year, but that figure fell by more than half in 2017 as its generic version eroded brand-name sales.
On Thursday afternoon, Mylan shares fell 0.2 percent, while those of Teva increased 6.8 percent.