(Reuters) – Walgreens Boots Alliance Inc said on Thursday it expanded its partnership with Kaleo Inc to include the company’s epinephrine auto-injectors for infants and toddlers in its pharmacies amid a national shortage of the emergency allergy shots.

Walgreens already offers two other doses of Kaleo’s emergency allergy shots, Auvi-Q, under a partnership that the drugstore chain entered with the company in September last year.

The company’s move comes days after Novartis AG said it would make its pre-filled epinephrine shots immediately available in local pharmacies across the United States.

Mylan NV, with its EpiPen, is the market leader for these devices, which are used to deliver epinephrine to counter severe allergic reactions to triggers such as peanuts or bee-stings.

But manufacturing delays at a Pfizer Inc unit, which produces all EpiPens sold globally at a single plant near St. Louis, have led to an acute shortage.

There is also traditionally high demand for the devices in the summer as families look to renew prescriptions ahead of the back-to-school season.

EpiPen has remained on the U.S. Food and Drug Administration’s list of drugs in shortage for more than a year, and Pfizer on Tuesday said it anticipates further supply shortages over the coming months.

Amneal Pharmaceuticals Inc, another maker of epinephrine shots, cut its full-year core earnings forecast on Wednesday, citing supply uncertainties of its auto-injectors made by a Pfizer plant in McPherson, Kansas.

(Reporting by Saumya Sibi Joseph in Bengaluru; Editing by Sriraj Kalluvila and Anil D’Silva)