Whiskey

 is a food item found in Fallout 3 and Fallout: New Vegas.

Fallout 3
Drinking it increases strength one point, which allows you to temporarily carry 10 extra pounds of items. By drinking this you run the risk of addiction, curable by doctors for a fee. It also boosts your charisma by 1 point while lowering your intelligence by 1 point.

Whiskey has all the same effects as vodka and beer. It is cheaper than vodka and found more often around the Wasteland.

Fallout: New Vegas
Whiskey is also a consumable item in Fallout: New Vegas

General
Whiskey provides the same effects as in Fallout 3, increasing Charisma and Strength by 1 while reducing Intelligence by 1. While in hardcore mode it also increases the player's dehydration level by 25.

Like all alcoholic beverages, the penalty to Intelligence for consuming whiskey is eliminated if the player has the Whiskey Rose perk. However, whiskey also provides a 2 point increase to the player's Damage Threshold with the Whiskey Rose perk.

As with any consumable item in Fallout: New Vegas, whiskey's effects are altered by the player's Survival skill, including the DT increase provided by the Whiskey Rose perk. With a Survival skill of 100 whiskey will provide triple the base positive effect: +3 to Charisma and Strength and +6 to Damage Threshold with the Whiskey Rose perk.

Variants

 * Dixon's Whiskey is a variant sold by Freeside merchant Dixon. It provides no Charisma boost and a penalty of 2 to Intelligence, and also has a high 50% addiction rate.
 * Irradiated Whiskey is, as the name indicates, radioactive. It provides the same effects as Whiskey with an added 10 points of radiation.  It can be found reliably in one place: the Camp Searchlight Fire Station, three bottles located in the kitchen.  A fourth bottle may rarely be found in the refrigerator inside Hell's Motel.

Both variants do not provide any increase to Damage Threshold when the player has the Whiskey Rose perk, though their penalties to Intelligence are still negated.