Anheuser-Busch and Miller Brewing have been hit with subpoenas in the US over their sales and marketing of their caffeinated alcoholic drinks brands.

A-B has confirmed to just-drinks today (21 February) that it has received the subpoenas from attorneys general for New York, Maine, Maryland, Arizona and Iowa regarding its Tilt and Bud Extra brands.

The brewer said that it is cooperating with the subpoenas, but that the formation and labelling for the two beverages had already been approved by federal authorities, prior to the subpoena being issued.

In August last year, the attorneys general of 29 US states wrote to the Alcohol and Tobacco Tax and Trade Bureau to quash what they called misleading health statements being made about alcoholic energy drinks. Products mentioned in the letter included A-B's Bud Extra, and Miller's Sparks and Sparks Plus.

A-B today said: "When these same AGs complained last summer to the … TTB …, (the) agency took no action and explained to the AGs that it had thoroughly reviewed, monitored, and approved the labelling and formulation of these drinks."

"Caffeinated alcohol beverages are nothing new," said A-B's vice president of communications and consumer affairs, Francine Katz. "Over the last few years adults have begun mixing caffeinated beverages like Red Bull with vodka, too, and drinking the many federally approved hard liquors that contain caffeine. Tilt and Bud Extra were introduced to compete responsibly in this beverage category.

"If the attorneys general truly believe that - despite the state and federal regulatory approvals - alcohol and caffeine should not be mixed, then they should use their powers to persuade these authorities to regulate or ban all such beverages, not just the lower-alcohol, pre-packaged ones."

No-one was immediately available at Miller Brewing for comment when contacted by just-drinks today.

Earlier this month, A-B unveiled plans to release a lime-infused extension to its Bud Light brand in the country. The brewer said that the move was a response to consumers' growing interest in flavoured drinks, as noted by the rising popularity of energy drinks and vitamin-infused water.