The dangerous synthetic supplement is marketed as a treatment for pain, anxiety and depression

Los Angeles health officials have issued a dire warning against the use of a synthetic Kratom supplement sold at some gas stations and smoke shops after three otherwise healthy people died from using the drug.

Three overdoses reported in Los Angeles have been tied to the potentially deadly Kratom compound known as 7-Hydroxymitragynine or 7-OH, Los Angeles County Department of Public Health officials said in a press release.

The victims, who were between the ages of 18 and 40, were all otherwise healthy. While alcohol was present in all of the cases, no other substances were identified as substantively contributing to their deaths, officials said.

Kratom and 7-OH products are made from the leaves of Mitragyna speciosa, a tree native to Southeast Asia. The synthetic supplement has become popular in the U.S. as a treatment for pain, anxiety and depression, even though its use is not regulated.

Leaves from the tree can be crushed and then smoked, brewed with tea, or placed into gel capsules. Products containing 7-OH are sold at gas stations, smoke shops and other retailers.

These products are often promoted as dietary supplements used to address a wide range of issues, including pain, anxiety, mood disorders, opioid withdrawal symptoms as well as energy/well-being.

They can be sold in various forms, including tablets, gummies, drink mixes, and concentrated ("enhanced" or "super") liquid extracts or shots for drinking, which "significantly increase its adverse and potentially life-threatening effects," health officials warned.

The products, often sold at U.S. gas stations and by online retailers, are often labeled as "plant alkaloids" or "alkaloid."

At low doses, 7-OH can have stimulant-like effects and at higher doses it can have opioid-like effects, health officials said.

"High doses of 7-OH and/or co-used with alcohol or other sedatives can cause severe respiratory depression and death. Again, they are unregulated and may contain unknown concentrations of 7-OH, increasing the risk of unintentional overdose," health officials said.

The Food and Drug Administration issued warning letters to multiple firms for illegal marketing of concentrated 7-OH products.

"There are no FDA-approved drugs containing 7-OH, and it is illegal to market any drugs containing 7-OH. Consumers who use 7-OH products are exposing themselves to products that have not been proven safe or effective for any usem," health officials said.

The Los Angeles County Department of Public Health says the safest course of action is to avoid using 7-OH or kratom products altogether.

However, officials offered some safety tips to avoid potential overdose or overdose-related deaths, including never using drugs alone, staggering drug use with others, avoiding mixing 7-OH with other drugs, and carrying naloxone.

Synthetic kratom drug now blamed for at least three deaths in California