Stinking nightshade, or one useful poison.
a.k.a. Hyoscyamus niger L. is one quite stinking herb. It is also quite toxic when raw and unprocessed.
You should never eat this plant and if you want to gather and dry it - use gloves and thoroughly wash your hands after this.
Gathered for drying are the leaves of the 2-year old plants. They are almost 3 foot tall and after they are fully blossomed on the second year, they got small basket-like fruits. (I don't know how the bees can collect this stinking pollens at all, but honey from this particular nightshade IS NOT poisonous :D ). You need to collect the leaves while the herb is blooming. This happens between June and September.
Drying is done at 40 degrees Celsius (104 F) and the leaves become grayish green.
This herb is very rich on Alkaloids and some cultures were smoking it on cigars to get "alternate state of awareness", but most often they have heartbeat, irritation, hallucination and other even less good things.
What is so good in this poisonous herb then?
It does help Rheumatoid pain, Gout pain in joints and neuralgia. An alcohol extract is made this way:
20-30 leaves of this herb are drowned in a bottle of alcohol. (Whatever cheap vodka or brandy you have left in the closet.)
Then it is left in a dark place far from sunlight for a week. The extract is ready when it paints the alcohol in amber (better use vodka).
Soak a cloth in the alcohol extract and put the cloth over the pain. It quickly calms the joint and nerve pain. Just don't forget to wash you hand after this.
It is also good for headache. Rub a small cloth soaked in the extract on your temples. The massage with the wet cloth will take the pain away and the general blood circulation in the head will be improved (the alkaloids have atropine-like action on nerves).
Again. Wash your hands. This herb is quite poisonous for mammals.