As markets historically become volatile during the month of September, where should investors put their money?
Despite a 15% rally over the past year, Firestone sees more upside in the veterinary healthcare company. Problems in biotech and drug pricing issues are not impacting this side of the business, according to Firestone. "With double-digit growth, we really like [Zoetis] here," she added on CNBC's Halftime Report.
Currently, Zoetis trades at 27 times forward estimates.
Firestone also recommends adding Charter Communications to your shopping list.
She sees potential in the acquisition of Time Warner Cable. "The cable operators are increasing their control because there is so much content available," she said.
Shares of Charter Communications have popped 35% over the past year.
—By CNBC Producer Bree Kelly. Follow her on Twitter @Bree_Kelly
Disclosure: Karen Firestone owns Zoetis & Charter Communication.