I'll try to help you. For additional info, there's my Cyber Sites for Herbs - if you find one that doesn't connect, please email me. The sting of nettle can be mitigated by rubbing the rash with leaves of yellow dock. The irritant is formic acid which is borne in hollow little hairs with swollen bases - boiling or drying the plant eliminates the irritant. Infusions of the plant should be well strained.
Mature leaves are coarse, bitter and mildly laxative.
Avoid with high blood pressure. The leaves are dried in the shade so that the green color is preserved. Material which turns brown while drying is useless. Tea of the dried leaves with honey and lemon used as a stimulant Increases flow of milk in nursing mothers. Tea as a rinse for dandruff.