A shortage of infant formula that began earlier this year continues to strain families who struggle with both availability and rising cost. Specialty formulas, used by babies and children with allergies, gastrointestinal issues, or other health challenges, have become especially hard to find.

Here’s what to know about the infant formula shortage:

Why is there a shortage of infant formula?

Problems with formula supply began when the COVID-19 pandemic disrupted production and delivery of ingredients. Along with toilet paper and hand sanitizer, formula was among the necessities families frantically stockpiled during the beginning of the pandemic, fearful they would not be able to leave their homes or find what they needed when they did get out.

Supply issues got much worse earlier this year, when the U.S. Food and Drug Administration issued a warning of bacterial infections linked to formulas from Abbott Nutrition, and the company issued a massive recall. Abbott, which produces popular formulas including Similac, Alimentum, and EleCare, was forced to close its formula manufacturing plant — the largest in the U.S. — over concerns of bacterial infection.

What’s being done about the shortage?

The FDA has said it is working with U.S. manufacturers to increase their supply of formula and “streamlining paperwork” to increase formula imports.

With FDA authorization, Abbott is releasing on a “case-by-case basis” some specialty formulas, which are critical for babies with allergies, dairy intolerance, or other medical complications and which have been especially hard to find. They are being provided free of charge, in coordination with physicians and hospitals, the Associated Press reported. Parents should talk to a pediatrician before using these formulas, since they were made during the time of the bacterial infection.

What should I do if I can’t find the formula I need?

Call your pediatrician’s office, which may have samples available to help in a pinch. Your pediatrician may be able to help identify alternative brands of formula that would be similar to your usual kind. Food banks, baby pantries, and charities may have formula in stock.

What should I do if I can’t afford formula?

Even when parents can find formula in stock, they might not be able to afford it. A 20-ounce canister of powdered formula can cost from $20 to $40, depending on whether you choose a brand name or generic. Specialty formulas cost even more.

Pennsylvania WIC and New Jersey WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) programs can help with formula for families that qualify. But be aware that these programs have also been hit by the formula shortage.

Food pantries, shelters, and charities may be able to provide free infant formula, if they have it in stock.

Can I make my own formula at home?

No. Medical providers and the FDA advise against homemade formula recipes. While it was common for parents to make their own formula before commercial powdered formulas rose in popularity in the 1960s and 1970s, doctors and dietitians say homemade formula does not have the correct balance of vitamins and nutrients, said Nicole Fragale, a registered dietitian and clinical nutrition manager at Nemours Children’s Health.

Can I add extra water to my baby’s formula?

No. This may seem like a harmless way to stretch supply, but adding extra water to formula can lead to emergency health issues, such as seizures and heart problems, Fragale said. Too much water throws off the balance of electrolytes in the formula, which can quickly affect a baby’s ability to function properly, she said.

Can I put infant cereal in my baby’s formula?

No. Adding infant cereal — a powdery mix of wheat, rice, or oats with vitamins — to bottles can be dangerous and the American Academy of Pediatrics advises against it. Bottles containing infant cereal can be a choking hazard because the food is thicker than babies are accustomed to — and possibly too thick for young babies to consume safely. When added to formula, infant cereal can absorb the nutrients in formula, making for an even less nutritious meal, Fragale said.