I’m playing the 7ed version of Masks of Nyarlathotep. I decided to have my character a laudanum user as he’s an opium addict, because I was certain there were rules about narcotics and drug addiction in Call of Cthulhu.
But now I can’t find any in the main rulebooks (I have 5th to 7th edition), investigator and keeper handbooks, or other sourcebooks and campaigns I have.
Are there any official (or unofficial) rules for PCs using narcotics and for addiction? If there are, which book are they in?
The rules don’t have be official or for 7E (I’ll convert or adapt rules from earlier editions).
For now, at the last session, myself and the GM decided to give my PC a penalty dice on skill and characteristic rules and movement, and to reduce the effects of Sanity rolls (sometimes he won’t make them, if he does the sanity costs might be reduced), when he’s under the influence of laudanum.