The vegetable saps and extracts of this heading are generally raw materials for various manufactured products. They are excluded from the heading when, because of the addition of other substances, they have the character of food preparations, medicaments, etc. The heading also excludes vegetable extracts which have been mixed or compounded (without the addition of other substances) for therapeutic or prophylactic purposes. Such mixtures, and similar medicinal compound extracts made by treating a mixture of plants, are classified in heading 30.03 or 30.04. That latter heading also covers simple vegetable extracts (whether or not standardised or dissolved in any solvent) when put up in measured doses for therapeutic or prophylactic purposes or in forms or packings for retail sale for such purposes