Standard dosages Western Herbs

The dosage is a matter of the prescriber

Usual doses for adults:

Loose herbs
Per cup: pour boiling water over 1 - 2 tablespoons of herbs and have it infused for at least 15 minutes. 
Per pot: pour boiling water over 1 - 2 tablespoons of herbs in a pot of stone, glass or enamel (not metal) and drink spread throughout the day.

Herbal capsules
3 x daily 4 capsules of 250 milligrams (initial dose)
3 x daily 2 capsules of 250 (maintenance dose)
3 x daily 2 capsules of 500 milligrams (initial dose)
3 x daily 1 capsule of 500 milligrams (maintenance dose)

Herbal tablets
3 x daily 4 tablets (at the beginning or in acute situations) of 300-350 mg
3 x daily 2 tablets (maintenance dose)

Dry extract-tablets or capsules
The dose is strongly dependent of the chosen concentration. As a rule apply: 3 x daily 50 mg/tabl or caps.

Tinctures
3 x daily 40 to 100 drops for tinctures 1:10 = 3 x daily 2 to 5 ml
3 x daily 20 to 50 drops for tinctures 1:5 = 3 x daily 1 to 2.5 ml

Syrups
3-5 tablespoons daily. 1 tablespoon = 15 ml

Dosage chart for children:

Rules for using:
Column C of this scale indicates the dosage in % of the adult dose, calculated to the body surface area. If one prefers to use the age, we read from column A to column C. More precisely, it is to take the weight, provided that the child is built normally. For this, one reads from column B to column C. If the child is abnormally proportioned, then one takes the average of the dosage to the weight (B to C), and to the length (D to C): connect the value of the weight (B) with the value of the length (D) and the point of intersection with column C gives the dose as a percentage of the adult dose.