How to tag a (cannabis) coffee shop?

I'd like to try to tag some "coffee shops" in the Netherlands. These shops sell cannabis. However, I couldn't find any good tag. In Amsterdam, a few are tagged, but as "shop=coffee", which is IMHO not very clear because it could easily suggest that they sell coffee (grains), which they don't. I guess the tag should also be able to represent places like "Medical lounges" in California.

Here are a few statistics on the tags that sound related:

• http://taginfo.openstreetmap.org/tags/shop=coffee : 187
• http://taginfo.openstreetmap.org/tags/shop=coffeeshop : 1
• http://taginfo.openstreetmap.org/tags/shop=cannabis : 1
• http://taginfo.openstreetmap.org/tags/shop=drug : 0
• http://taginfo.openstreetmap.org/tags/shop=headshop : 8
• http://taginfo.openstreetmap.org/tags/shop=smartshop : 3

I'd rather go with shop=cannabis, does it sounds good? Any better suggestion?