Last Updated: November 10, 2026
The penicillin cocktail is made with 2 ounces of blended Scotch, 0.75 ounce of fresh lemon juice and 0.75 ounce of honey-ginger syrup, shaken with ice, strained over a large cube, and topped with a quarter ounce of smoky Islay Scotch floated on the surface. It is a modern classic that balances sweet, sour, spicy and smoky in one glass, and it is easy to make once you have the syrup prepared.
What Defines a Penicillin
The drink works like a whisky sour with two upgrades. Honey replaces simple syrup for a floral, round sweetness. Fresh ginger gives warmth and a gentle heat. Then the Islay float adds peat smoke on the nose without taking over the palate, so each sip begins with smoke and finishes with ginger and lemon.
The balance is the entire point. Too much honey makes it cloying, too much ginger turns it harsh, and too much peated Scotch overpowers the rest. Measure carefully and the cocktail rewards you.
Honey-Ginger Syrup
Make the syrup first so it has time to cool.
- Peel and thinly slice about 3 inches of fresh ginger root, about 2 ounces.
- Combine 4 ounces of honey and 4 ounces of water in a small saucepan.
- Add the ginger and bring to a gentle simmer over medium heat, stirring until the honey dissolves.
- Simmer for about 5 minutes, then remove from the heat.
- Let the syrup steep for 20 to 30 minutes for a stronger ginger flavor.
- Strain into a clean jar, discard the ginger, and refrigerate. It keeps for roughly two weeks.
Ingredients
- 2 oz blended Scotch whisky
- 0.75 oz fresh lemon juice
- 0.75 oz honey-ginger syrup
- 0.25 oz peated Islay Scotch, for the float
- Ice, including one large cube for serving
- Candied ginger or a lemon wheel, for garnish
Instructions
- Add the blended Scotch, lemon juice and honey-ginger syrup to a cocktail shaker.
- Fill the shaker with ice and shake hard for 12 to 15 seconds.
- Place a large ice cube in a chilled rocks glass.
- Strain the shaken drink over the cube.
- Slowly pour the Islay Scotch over the back of a bar spoon so it floats on top.
- Garnish with a piece of candied ginger on a pick, or a lemon wheel, and serve right away.
Choosing Your Whiskies
The base should be a smooth blended Scotch with a light to medium body. Heavily sherried or very smoky bases can clash with the honey. For the float, any peated Islay single malt will do, and since only a quarter ounce is used, one bottle lasts a long time. If you do not want to buy a separate bottle, a mini or a small pour from a friend’s collection is enough.
Balance Adjustments
| If the drink tastes… | Adjust by |
|---|---|
| Too sweet | Add 0.25 oz more lemon juice |
| Too sour | Add 0.25 oz more syrup |
| Not spicy enough | Steep the ginger longer or add a small piece of muddled fresh ginger |
| Too smoky | Use a half-teaspoon float or lightly rinse the glass instead |
| Too watery | Shake for less time and use large, dense ice |
Variations
Bourbon Penicillin
Use bourbon as the base and omit the Islay float. The result is sweeter, with vanilla and caramel notes, and closely resembles a gold rush with ginger.
Mezcal Float
Replace the Islay Scotch with mezcal. It produces a different kind of smoke, more roasted agave than peat.
Hot Penicillin
Combine the blended Scotch, lemon juice and syrup with 3 ounces of hot water in a mug. Skip the shaking. It becomes a warming drink for cold evenings.
Spiced Version
Add a pinch of cayenne or a thin slice of fresh chile to the shaker for extra heat.
Garnish and Glassware
Use a double rocks glass with one large cube. Candied ginger is the classic garnish, offering a chewy, sweet bite that matches the syrup. A lemon wheel or twist is a lighter alternative. Pour the float last so the aroma hits your nose with each sip.
Technique Notes
Squeeze the lemon juice just before shaking. Citrus juice dulls within a few hours, and the cocktail relies on its brightness to offset the honey. Use a fine strainer or a tea strainer on top of the shaker’s strainer if you want a perfectly clear drink without ginger fibers or ice chips.
When floating the Islay Scotch, hold the bar spoon just above the surface with the back of the bowl facing up, and pour slowly. The whisky is less dense than the shaken drink, so it spreads across the top as a thin layer. If it mixes in, the drink is still fine, just less aromatic at first sip.
Honey syrup thickens in the refrigerator. Let it sit at room temperature for a few minutes, or stir it in a warm water bath, before measuring so you pour an accurate 0.75 ounce. A cold, sticky pour often leaves syrup behind in the jigger and makes the drink tart.
If you make several drinks, rinse the shaker between rounds. Leftover honey can cling to the walls and throw off the next batch.
Food Pairings
- Smoked salmon: The smoke in the float echoes the fish.
- Sharp cheddar: Rich and tangy cheese stands up to lemon and ginger.
- Roast chicken: Honey and lemon complement herb-roasted poultry.
- Spiced nuts: A simple snack that suits the ginger warmth.
- Shortbread: Buttery biscuits balance the drink’s acidity.
Making It for a Group
Because the syrup and Scotch can be measured ahead, a penicillin is manageable for small gatherings. Pre-mix the blended Scotch and honey-ginger syrup in the right proportions, for example 16 ounces of Scotch with 6 ounces of syrup, and keep the bottle in the refrigerator. When a guest orders, measure 2.75 ounces of the mix, add 0.75 ounce of fresh lemon juice, shake with ice and finish with the Islay float. This keeps the lemon fresh while saving prep time.
FAQ
What does a penicillin cocktail taste like?
It tastes bright and lemony first, then honeyed and gently spicy from ginger, with a lingering peaty smoke from the Islay float. It is balanced between sweet and tart.
Do I have to use an Islay float?
No. The drink is still good without it, but the float provides the signature aroma. If you do not have peated Scotch, you can leave it out and increase the ginger slightly.
Can I use bottled honey syrup?
You can, but homemade ginger syrup is better because the fresh ginger flavor fades in commercial products. Plain honey syrup made with equal parts honey and warm water plus a few slices of ginger is a quick fix.
Is the penicillin cocktail medicinal?
No. Honey, lemon and ginger are flavors people often associate with comforting home remedies, but the drink is an alcoholic cocktail meant purely for enjoyment.
Please drink responsibly and enjoy alcohol in moderation.
6 Best Gifts for Nurses (November 2026)
Java Fern Care Guide: How It Grows and What to Watch For
