The prices of three common generic drugs for heart failure vary considerably among retail pharmacists, according to an analysis 153 chain and 22 independent pharmacies in Missouri and Illinois.

Guidelines recommend each of the three medications (digoxin, lisinopril and carvedilol) for patients with heart failure.

Lead researcher Paul J. Hauptman, MD, of the Saint Louis University School of Medicine, and colleagues published their results online Nov. 15 in JAMA Internal Medicine.

The findings were also presented in an oral abstract session at the American Heart Association Scientific Sessions in New Orleans.

The researchers identified pharmacies in 55 zip codes in Missouri and Illinois and reached out to them during a three-week period in May 2016. They asked the pharmacies for the costs of digoxin (0.125 mg per day and 0.25 mg per day), lisinopril (10 mg per day and 40 mg per day) and carvedilol (6.25 mg and 25 mg twice daily) for 30- and 90-day supplies.

All of the prices were based on patients not having insurance. The researchers mentioned that an estimated 7.3 million people in the U.S. who have cardiovascular disease are uninsured.  

The researchers also used U.S. Census Bureau data to determine median annual income based on zip codes. The median annual income was $53,122, while income ranged from $10,491 to $112,017.

Only one of the chains had consistent pricing in its stores, according to the researchers. For all of the drugs, there was a wide range of prices, as well.

The median prices for 30-day supplies were $40.19 for low-dose digoxin (range of $12.19 to $94.99); $40.19 for high-dose digoxin (range of $4.00 to $305.99); $9.99 for low-dose lisinopril (range of $3.00 to $80.59); $14.18 for high-dose lisinopril (range of $4.00 to $87.59); $14.76 for low-dose carvedilol (range of $4.00 to $135.99) and $14.47 for high-dose cardvedilol (range of $4.00 to $73.81).

Meanwhile, the median prices for 90-day supplies were $114.99 for low-dose digoxin (range of $30.89 to $284.99), $114.99 for high-dose digoxin (range of $10.00 to $910.99), $17.37 for low-dose lisinopril (range of $6.79 to $205.99), $34.25 for high-dose lisinopril (range of $6.75 to $223.95), $36.95 for low-dose carvedilol (range of $6.00 to $379.99) and $41.23 for high-dose cardvedilol (range of $6 to $208.44).

The researchers mentioned that the pharmacy type was not significantly associated with pricing for drug, dose, supply or combinations. The pricing also did not vary significantly by state or by median annual income.

“The retail pharmacy—rather than drug dose, duration of therapy, pharmacy ownership, or pharmacy location—was the primary cost driver,” the researchers wrote. “Variability remained when all three [heart failure] drugs were bundled in a single purchase within a given pharmacy. Digoxin, the oldest cardiovascular medication available, was paradoxically the most expensive.”