About nine months ago, Mr. Hubig started experimenting with CBD oil at the encouragement of his brother, who has been in the cannabis industry for more than two decades. After a month or so, Mr. Hubig figured out which dosage felt right, and now estimates that his stress level has been reduced by at least half.

“Being high-strung and nervous and then having a kid, it’s like — holy smokes,” said Mr. Hubig, who works up to 80 hours a week. “I was just so worried about everything.”

[Enjoying this article? Sign up for the NYT Parenting newsletter here to get real stories like this, evidence-based guidance and more in your inbox every Wednesday.]

CBD use is growing among all adults in the United States, not just parents. The Brightfield Group, a cannabis market research firm, says CBD sales are expected to reach $22 billion by 2022. But is it safe to use? So far, the Food and Drug Administration has approved only one drug containing CBD: Epidiolex, which is used to reduce seizures associated with two rare forms of epilepsy. The agency recently announced that it is holding a public hearing at the end of May to gather information about the safety, manufacturing, product quality and marketing of cannabis or cannabis-derived compounds, including CBD.

The chemical is making headlines in part because of a new law. The 2018 farm bill legalized the production of hemp, which it defined as cannabis containing less than 0.3 percent THC, a move that is expected to help CBD vendors. But the F.D.A. said on its website that it does not permit CBD to be sold as dietary supplements or in food that crosses state lines, and has sent warning letters to several companies marketing products containing CBD.