Addicted to Nuka Cola:

Addicted to Nuka Cola is of the negative traits.
It has a value of -1

The description is as follows:

Addicted to Nuka Cola:
Served warm and flat or ice cold – you can't get enough of the most popular soft drink of both the prewar time and the post war time.
The last time you tried to go two days without this sweet caffeinated nectar, you shook so bad at the evening of the second day, that your friends had to be real careful giving you the first few sips.
Without at least a liter a day of Nuka Cola (we're no bean counters here, three standard 0,33 liter bottles count as a full one) this character gets the shakes and can't concentrate anymore.
All tests on skills are handicapped by 25 points. The cold turkey would last for three days. The handicap on the second day is -40. On the third day only -15.