What counts as strong alcohol for potion refilling?

Solution 1:

In the Witcher 3 the base you can refill on seems to be: Alcohest

There is also:

• Dwarven Spirit

• Temerian Rye
• Redanian Herbal
• Nilfgaardian Lemon

These were confirmed already.

You get it pretty early on in the game and it is pretty common. You can also buy it from Brams Shop in White Orchard

This is how it looks in the game:

If you are interested in some beverages that were used to brew potions in previous games and are considered hard liquor/strong alcohol in the Universe please check the list below.

Top Quality Bases

• Alcohest
• Azoth
• Mandrake Cordial
• Wormwood spirit
• Wyvern Blood Spirit
• White Gull

High Quality bases

• Cherry Spirit Cordial
• Dwarven spirit
• Plum Cordial
• Temerian spirit
• Zerrikanian spirit

Standard bases

• Local pepper vodka
• Nilfgaardian Lemon
• Redanian Herbal
• Soldier's hooch
• Temerian Rye

Solution 2:

According to various "tips & tricks" and guides found on the web, the general consensus seems to be that the item that is used for this is Alcohest. However, it appears that other alcoholic items will also work, if you're out of Alcohest.

When you meditate with Alcohest in your inventory, the meditation screen will notify you that your supplies have been replenished using that Alcohest. Once you run out of Alcohest, it will use other strong alcohol, like Dwarven Spirit or Pepper Vodka. See this post for reference as well. The game will default to Alcohest, and use the other items in order of sorting in your inventory.

I haven't actually tried this myself yet: but it seems that anything stronger than beer/wine would work, though an exact definition remains absent due to the many different items in the game.

Solution 3:

I just tried now which alcohol works by dropping whatever was used during meditation, drinking some potions again and meditating again. It is very likely I don't have all possible strong alcohols in my inventory right now, but these are the ones that could be used for refilling:

• Alcohest
• Dwarven Spirit
• Temerian rye
• Redanian herbal
• Nilfgaardian lemon

They were used in this order, Alcohest is the first choice, and if not available the next one on the list is used.