Image of a martini cocktail on a bar

It’s a tale of two guidelines for consuming alcohol while taking methotrexate (MTX).

“Alcohol significantly increases the risk for liver damage while taking methotrexate,” notes the American College of Rheumatology. “Alcohol should be avoided.” And yet, patients on MTX can consume alcohol provided they do so “well within the UK national recommendations,” according to the British Society for Rheumatology, which didn’t elaborate on those limits.

“The ACR guidance comments that regular alcohol consumption should not occur since there are ‘no data about the quantity of alcohol that can safely be consumed with MTX,’” write the authors of an Annals of the Rheumatic Diseases study. “Previous studies have not consistently demonstrated an association between increased alcohol consumption and hepatotoxicity or liver damage; yet, it is clearly biologically plausible that there may be an additive.”

As many patients enjoy drinking modestly, they may either abstain from alcohol while taking MTX or avoid taking MTX, “a potentially beneficial drug,” write the University of Manchester’s William Dixon and colleagues. “If patients do drink alcohol alongside MTX, even in moderation, they anecdotally describe feeling anxious or ill at ease. Understanding whether there is a safe amount of alcohol that can be consumed alongside MTX, and what that amount is, would significantly aid informed decision-making.”

Dr. Dixon and colleagues studied 11,839 RA patients — from a study, begun in 1987, which includes 8 percent of the UK population — increasing their weekly alcohol consumption. Patients experienced 530 transaminitis episodes over 47,090 person-years. Researchers defined transaminitis as three times above the normal liver enzyme limit (suggesting liver damage).

The researchers found that consuming between 15 and 21 weekly units of alcohol was associated with a possible increased risk of hepatotoxicity, while more than 21 units significantly increased transaminitis rate.

[Learn more about units of alcohol, including differences in the ways different countries measure a standard drink, see here.]

“This is the first large-scale study to provide quantifiable estimates of the risk of different levels of alcohol consumption while taking methotrexate long-term,” observes MedPage. It adds that 78 percent of the patients studied were mild drinkers — fewer than seven drinks per week — while 8 percent tended to consume more than 14 drinks a week.

“Our study was conducted only in patients with RA and thus cannot be automatically generalisable to other populations,” the authors warn. “Previous data have suggested that patients with psoriasis may have higher incidence of liver disease in general compared with patients with RA, and therefore confirmatory studies would be required in these patient groups.”

“Inclusion of acceptable alcohol levels into clinical guidelines and patient information leaflets may well improve informed decision-making, clinical outcomes, reduce decision conflict and improve overall quality of life,” they added.

[See a CNN story from 2010 about moderate alcohol consumption and RA.]

In February 2017, John Cush, a Dallas-based rheumatologist, ran a web survey about MTX and alcohol, which was published on Rheumnow.com. More than 90 percent of respondents self-identified as rheumatologists, and 50.5 percent said they allow patients taking MTX to take one to three alcoholic drinks per week.

Slightly more than 18 percent told patients not to drink at all, while nearly a quarter allowed one to three drinks per month.