DEERFIELD, Ill. — Walgreens has begun providing the opioid overdose antidote naloxone without a prescription at all of its pharmacies in Louisiana.

Administered by injection or nasal spray, naloxone can be obtained without a doctor’s prescription in more than 150 Walgreens pharmacies in Louisiana, in accordance with state pharmacy regulations.

The medication can be used in the event of an overdose to reverse the effects of heroin and other opioid drugs.

“By making naloxone available without a prescription, we are making it easier for Louisiana families and caregivers to help their loved ones by having it on hand in case it’s needed,” Rob Braley, Louisiana regional health care director for Walgreens, said in a statement. “As a pharmacy, we are here to help people, and we are committed to making naloxone more accessible in the communities we serve.”

In February, Walgreens unveiled plans to make naloxone available without a prescription in 35 states and Washington, D.C. The drug chain since then has enabled no-prescription access to naloxone at over 4,300 pharmacy locations in 24 states.

Walgreens said that when the program rollout is complete, naloxone will be available without a prescription in more than 7,000 of its nearly 8,200 stores.

States where Walgreens offers naloxone without a prescription include Alabama, Colorado, Idaho, Illinois, Indiana, Louisiana, Maryland, Massachusetts, New Hampshire, New Jersey, New Mexico, New York (including Duane Reade), North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, Texas, Utah, Vermont, Virginia, Washington, Wisconsin.