It's made from infused pine needles, mixed with cardamom and lemon peel and the end result is a delicate bitter-sweet soda.
Traditionally tonics have been concocted from all kinds of health affirming ingredients.
The tonic in a gin and tonic for instance was once laced with quinine; it acted as a treatment against malaria in colonial times when Europeans were stationed in faraway regions where they had no natural resistance to the parasite.
And now there's "Estonic Soda", a tonic infused with Christmas spruce that's been concocted on an Estonian island.
When the holiday season ends some trees from the Baltic region are shipped to a very distinct family-run distillery on Saaremaa to be recycled into a spruce-flavoured tonic.
It's made from crushed and infused pine needles, mixed with cardamom and lemon peel.
The end result is a delicate bitter-sweet soda, enriched with a Christmassy aroma.
"Spruce is really known across the Nordics. For centuries, it has been used, and it's really good for the vitamins and minerals, it has a lot of vitamin C and vitamin D in it," Tarmo Virki, the founder of Lahhentagge Distillery told Euronews.
"And of course, these times when people are trying to fight the pandemics it's even more in demand."
Three years ago the company recycled its first Christmas tree from a local town hall square. Then they recovered one from the Estonian mainland.
Now, spruces are being picked up from town squares in the Finnish capital, Helsinki and the Latvian resort town of Jurmala.
But not all of some 50 million Christmas trees that adorn Europe every year can end up in these bottles.
The smaller indoor variety, found in homes across the continent, are often too dried out.
Their larger cousins, erected in Nordic town centres, retain more moisture and make better ingredients for this unique beverage.
And just one spruce can be used to produce up to 10,000 litres of tonic water laced with Christmas spirit.