A pharmacy technician counts pills before filling a prescription. (U.S. Air Force/Bobby Jones)

Prescription drug costs for Tricare users are set to rise Jan. 1, some by as much as 42%.

Effective Jan. 1, 2020, a 90-day supply of generic drugs received through the program's Express Scripts mail-order pharmacy will increase from $7 to $10. Co-pays on brand-name drugs received through the mail will go from $24 to $29; the price rises from $53 to $60 for non-formulary drugs.

Generic drug prescriptions filled at retail pharmacies will see the cost rise from $11 to $13 for a 30-day supply, while the same supply of brand-name medications will increase from $28 to $33. Non-formulary drugs -- those not on Tricare's list of fully covered medications -- will go up from $53 to $60.

Prescriptions filled on base will continue to be free.

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The price increases, while normal in the civilian world, are fairly new to Tricare. They were mandated by Congress as part of the 2018 National Defense Authorization Act in an effort to bring the amount users pay into line with the actual costs of prescription drugs, which have been skyrocketing in recent years.

Per that law, these annual increases will continue until at least 2027.

Out-of-network pharmacy costs are also increasing. Users who buy drugs at those pharmacies or overseas must first meet their annual deductible, which varies by Tricare plan.

Tricare Prime users pay a 50 percent cost share for the drug after their point-of-service fee. All other users, except active-duty troops, will pay 20 percent of the total cost or $29, whichever is higher, for drugs on the formulary. They will pay 20 percent of the cost or $60, whichever is higher, for off-formulary drugs. Active-duty troops will be reimbursed for any out-of-network pharmacy fees.