After years of relative stability, U.S. antimicrobial sales for food-producing animals rose in 2024. According to the FDA’s 2024 Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals, sales of medically important antibiotics increased 16% compared with 2023, marking a notable reversal after nearly a decade of plateauing or declining volumes.
When it comes to cattle, this report raises an important question: Does this increase reflect a temporary response to disease and production pressures, or does it reflect a more durable change in antimicrobial purchasing patterns?
FDA Antimicrobial Sales Trends Show a Clear Rebound
FDA data shows antimicrobial sales for food-producing animals peaked in 2015, followed by sustained declines after growth-promotion indications were removed and veterinary oversight expanded. From 2016 through 2023, total sales largely stabilized or declined modestly, including a 2% decrease from 2022 to 2023.
This pattern changed in 2024. Total antimicrobial sales increased 16% year over year, representing the largest single-year increase since regulatory reforms took effect. While overall volumes remain approximately 27% below 2015 levels, the size and rebound stands out against nearly a decade of gradual reduction.
Which antimicrobial classes increased in 2024?
The 2024 increase was not evenly distributed across antimicrobial classes. Several medically important categories accounted for most of the growth:
- Tetracyclines: ~20% increase; remains the largest class by volume
- Aminoglycosides: ~37% increase
- Lincosamides: ~11% increase
In contrast, penicillins declined by approximately 14%, despite remaining among the most commonly sold classes overall.
The concurrent rise across these classes likely reflects increased disease pressure and production challenges. While FDA sales data cannot identify clinical drivers, the pattern points toward greater reliance on core therapeutic drugs during a challenging production year.
Looking across species, 41% of medically important antimicrobial sales in 2024 were intended for cattle, 43% for swine, and 16% for poultry.
What the Data Show for Cattle
When looking specifically at cattle, tetracycline sales increased ~19%, aminoglycosides increased ~38%, sulfonamides increased ~24% and cephalosporins increased ~26%.
These antimicrobial classes are foundational tools in cattle medicine, particularly for respiratory and systemic disease. Tetracyclines are widely used across beef and dairy systems for bovine respiratory disease, anaplasmosis and reproductive tract infections, supported by broad-spectrum activity, multiple formulations and long-standing familiarity in practice. Aminoglycosides are used more selectively but are important for treating gram-negative and enteric infections, often in more severe cases. Lincosamides are commonly used for respiratory disease and certain anaerobic or foot infections.
To provide additional context, the FDA report also includes biomass-adjusted antimicrobial sales, including an interactive dashboard, which accounts for changes in animal population size and average live weight. This data could be a more meaningful indicator of antimicrobial use intensity.
Biomass-adjusted sales of aminoglycosides, amphenicols, cephalosporins, fluoroquinolones, lincosamides, sulfonamides and tetracyclines for cattle all increased from 2023 to 2024 representing a higher intensity of use.
Swine Data Also Showed Increases
The sale of medically important microbial drugs for use in swine increased 13% from 2023 to 2024. While annual sales for swine have been slowly increasing since 2020, this jump is much larger than it has been in previous years.
Looking at specific drug classes, Aminoglycoside sales increased ~25%, fluoroquinolones increased ~49%, sulfonamides increased ~15%, tetracyclines increased ~15%, and lincosamides increased ~13%.
In swine, aminoglycosides and sulfonamides are frequently used to manage enteric and respiratory conditions. Fluoroquinolones and tetracyclines are critical for addressing complex swine respiratory diseases and systemic infections, while lincosamides are often specifically targeted at combating swine dysentery, mycoplasmal pneumonia and infectious arthritis.
Biomass-adjusted sales of these drugs for swine all also increased from 2023 to 2024.
Sales Data are not the same as on-farm use
A critical point emphasized by FDA is sales and distribution data do not directly measure the actual use of antimicrobial drugs on farms. These drugs can be purchased in anticipation of use, be used at a later date or held in inventory for future needs. There is no national system in place that measures antimicrobial use across animal production sectors in real time. Year-to-year fluctuations in sales can reflect many factors including animal health needs, changes in livestock populations and evolving production practices.
Despite the rebound in 2024, food-animal antimicrobial sales remain significantly lower than a decade ago. Even so, the data reinforce the need for stewardship that balances effective disease control with antimicrobial resistance considerations, guided by clinical judgment and herd-level decision-making.
