NSAIDs Surpass Opioids as Top Drug Class Prescribed in California's Workers Comp System

Nonsteroidal anti-inflammatories (NSAIDs) have passed opioids as the most common drug group prescribed to injured workers in California, while payment data show that both dermatological medications and anticonvulsants now rank ahead of opioids in terms of total reimbursements, according to a report examining trends between 2009 and 2018.

The study from the California Workers’ Compensation Institute (CWCI) found the share of spending on anticonvulsants tripled from 4.8% to reach 15.2% by the first half of 2018, putting them ahead of opioids as the second most costly drug group.

The data in “California Workers’ Comp Prescription Drug Utilization and Payment Distributions, 2009-2018: Part 1” comes from 5.75 million prescriptions dispensed to California injured workers. The report examines changes in the prescription and payment distributions among therapeutic drug groups, identified trends in the use of generics, and determined average amounts paid for drugs within each drug group over the past decade.

Most of the growth in anticonvulsant’s share of drug payments occurred over the past 4 years, coinciding with the reduction of opioid prescriptions, possibly suggesting the use of certain anticonvulsants, such as gabapentin and pregabalin, in place of opioids. Anticonvulsant prescriptions used in California workers’ comp are heavily concentrated in the 2 drugs. Pregabalin is only available as a brand drug (sold as Lyrica), and it accounted for nearly 75% of the spending in anticonvulsants in the first half of last year. The drug is slated to become available as a generic later this year.

Opioids fell to 18% of the prescriptions filled in the first half of 2018, down from 20.2% in 2017 and 30.5% a decade ago. Opioids have faced tighter scrutiny via utilization review and independent medical review with restrictions by payers, medical provider networks, pharmacy benefit managers, and within the formulary that providers and patients in the state workers comp system must follow.

NSAIDs surpassed opioids as the top drug group in California workers’ compensation in 2016, when NSAIDs were 27.6% of prescriptions filled and opioids were 22.9%. Their share has continued to climb, reaching 31.7% of the drugs dispensed to injured workers in the first half of 2018.

Anticonvulsants’ share of prescriptions rose 136.6%, more than doubling from 4.1% in 2009 to 9.7% in the first half of 2018. The report said the increase is likely from their growing use as a nonopioid alternative to treat neuropathic pain, such as gabapentin and pregabalin. The 2018 data show anticonvulsants were the third most prescribed drug group, moving ahead of muscle relaxants, which became more restricted under the formulary that took effect on January 1, 2018.

The report also found shifts in the distribution of prescription payments in California workers’ comp. A decade ago, dermatological products accounted for 10.1% of the total drug spend and were the fourth most costly drug group behind opioids, NSAIDs, and ulcer drugs. That share rose to 17.6%, making dermatologicals the top drug group in terms of total payments in the first half of 2018.

The report said that previous years’ growth in dermatological payments was largely driven by high-cost “custom” pharmacy compounded drugs, but that growth was curbed by state legislative changes as well as indictments involving compounded drug kickbacks. Two other factors were cited for the current growth in dermatologlical payments:

• An increase in high-cost, mass-produced private label topicals containing 1 or more active ingredients (eg, capsaicin, lidocaine, menthol, or methyl salicylate) commonly found in over-the-counter topical analgesics, which are marketed to physicians, and
• An increase in payments for topicals containing a prescription NSAID.