By Dina Kupfer

SACRAMENTO (CBS13) — Parents across the country are growing increasingly worried about where their baby’s next bottle will be coming from.

More than 43% of the most popular brands are sold out at stores across the nation, according to Datasembly. But what can parents do if they can’t get their hands on their baby’s formula?

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“This formula shortage is absolutely an emergency for the united states; however, here in California, our supplies of formula are better than in other states across the country,” said Dr. Adrienne Hoyt-Austin.

Dr. Hoyt-Austin is a lactation consultant with UC Davis Children’s Hospital, and while she says we aren’t in dire straits in California, we are hearing from local families who are concerned.

“We are having so much trouble finding the formula my granddaughter uses she is only four months! I don’t know what we are going to do my poor daughter in law was crying this morning she is so worried!” Monica Rivas from Natomas wrote on Facebook.

Dr. Hoyt-Austin says parents of formula-fed babies should not be afraid to try a new brand. The vast majority of babies are on typical cow’s milk formula, and, she says, most ingredients are similar.

“For those families who are feeding those types of formula, you really can use any formula available at the store, you want to stay away from hydrolyzed formulas, which are formulas specific for babies who absolutely critically need them,” she said.

Dr. Hoyt-Austin says making your own formula at home is “extremely unsafe” and you shouldn’t dilute the formula you have to make it stretch.

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“If you dilute the formula, it can cause electrolyte imbalances, or salt imbalances, in the body that are extremely dangerous for babies,” she said.

Milk banks can be a safe alternative.

“Milk banks here in the U.S. are extremely safe,” Dr. Hoyt-Austin said.

Dr. Hoyt-Austin says breastmilk is heavily tested for transmissible diseases, and women must have a clean bill of health from their doctor to donate their milk.

But human milk is very expensive and out of reach for many families. The Human Milk Banking Association of North America is made up of 30 nonprofit milk banks across the U.S. and Canada. They are encouraging more women to donate their breast milk, which is distributed to local milk banks and pharmacies.

So, if you are nursing and/or pumping, how can you boost your own milk supply?

“It’s increasing how frequently they’re expressing that breastmilk,” Dr. Hoyt-Austin said. “You can certainly increase your hydration and your nutrition, but it’s really expressing that milk that’s the most important thing.”

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Parents can also look for formula samples at your pediatrician’s office. Most pediatricians’ offices stock samples that can tide parents over for a short period of time until stores are able to restock.