The penicillin cocktail is so well-known on the global drink scene that most assume it’s a classic.

It does follow the traditional pre-prohibition recipe format (less than four ingredients). The only clue that it’s a recent creation is the use of an exotic sweetener.

Made of two kinds of scotch (a peaty and blended one), lemon juice, and honey-ginger syrup and served in a rocks glass, Penicillin is a smoky riff on a Whiskey Sour. Although medicinal penicillin was first discovered in 1928, the world would have to wait nearly a century later for its namesake libation.

The Discovery

In 2005 at New York City’s Milk & Honey cocktail lounge, while experimenting with The Peat Monster (a scotch by Compass Box), Australian bartender Sam Ross made an interesting discovery. He mixed in some ginger juice and floated the Islay Malt atop a Gold Rush cocktail, another whiskey-based modern classic invented at Milk & Honey. Eventually, he named it Penicillin and put it on the menu.

What’s in a Name

Because the drink uses not one, but two types of scotch, was the name a nod to the Scottish scientist Alexander Fleming, who discovered the world’s first antibiotic? That may have been a factor, but according to Ross, the name is a tongue-and-cheek reference to its cure-all properties.

Rise of Fame

Once it landed on the bar’s menu, it became an instant hit with clients and bartenders alike. Word quickly spread as Milk & Honey (now shuttered) was one of America’s most influential bars in the craft cocktail movement and speakeasy revival. But it wasn’t until a few years later that it found its permanent place among go-to drinks of all time. In 2007, Ross headed to Los Angeles to help open a few bars. The easy sipper’s popularity spread even faster, with bars on both coasts adding it to their cocktail menus.

“Friends send me pictures of Penicillin on the menu from all over,” Ross said in a 2013 Time interview. And there have been many Penicillin riffs since; in fact, it’s been heralded as the “most riffed-on modern classic.” The Medicina Latina, created by Marcos Tellos in Los Angeles, substitutes lemon with lime and the scotches with mezcal and tequila. London’s The Shrub & Shutter added molecular elements with charred honey, oak smoke, and egg white. Over the summer, Atlanta’s AMER served Penicillin Pops, swapping ginger syrup with ginger beer, and Brooklyn’s Diamond Reef offered frozen “Penichillins” from a slushie machine. Slushy Penicillins were the favorite drink over the summer at Bible Club Pdx in Portland, too.

Making a Penicillin

Making a Penicillin

It’s a comforting thought that the drink that cures what ails is readily available across the globe in so many variations.

Ready to try it out? Check out the original Penicillin recipe.

Penicillin Cocktail

Penicillin Cocktail

Penicillin Cocktail 

Ingredients:

  • 2 oz. Blended Scotch Whisky
  • 1/4 oz. Smoky Islay Single-Malt Scotch Whisky
  • 3/4 oz. Fresh Lemon Juice
  • 3/4 oz. Honey Syrup
  • 2-3 slices of Fresh Ginger
  • Candied Ginger (for garnish)

Preparation: Muddle fresh ginger in shaker and add remaining ingredients, except Islay whisky.

Fill the shaker with ice and shake to chill; double-strain into an ice-filled rocks glass. Float whisky on top and garnish with candied ginger.