(CNN) -- Parents of young children who get the flu may have a hard time finding an antiviral drug to help treat them.
Genentech, which makes the antiviral known as Tamiflu Oral Suppression (Tamiflu OS), the liquid version of the drug, says there have been temporary delays in new shipments.
"We experienced an increase in demand due to a higher prevalence of influenza Type B in the season," Genentech spokeswoman Tara Iannuccillo said in an e-mail. "We are working to expedite new shipments of Tamiflu OS to distributors as new supplies become available."
Tamilflu OS is typically prescribed for children younger than 13 or for people who have trouble swallowing pills. It is the only flu drug for infants approved by the Food and Drug Administration. The FDA granted that approval for infant use in December.
Some 30 million children worldwide -- 6.9 million in the United States -- have received a prescription for it since Tamiflu was first approved in the United States over 13 years ago, according to Genentech. Given within the first couple of days of infection, it can ease flu symptoms and shorten the duration of the illness.
There have been some shortages of the drug at pharmacies, said Mike DeAngelis, a spokesman for CVS Caremark Corp. However, there is an alternative for children, he said.
"Patients can speak to their pharmacist about the option of having the pharmacy compound Tamiflu capsules into a liquid," DeAngelis said in an e-mail.
Walgreens spokesman Jim Cohn said it, too, has experienced some shortages.
But pharmacists can "compound as needed to continue filling prescriptions for the liquid Tamiflu to meet the needs of patients during this flu season," he said.
A pharmacist, for instance, would be able to take the capsule version of the drug and suspend it in Ora-Sweet to make a liquid version of the drug. Ora-Sweet is a sweet and thick syrup that is the base of many liquid versions of children's medicine.
There is an adequate supply of the capsule form of Tamiflu, according to the manufacturer. There have been shortages of the capsule in the past, particularly during the H1N1 pandemic in 2009, and another shortage in 2011.
"The FDA is continuing to monitor this closely and will post information on our website. We are also working with the company to increase supplies," said Sarah Clark-Lynn, a spokewoman from the FDA Office of Public Affairs.
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