Design Comments: The Substance entity is used to describe any material that functions as an ingredient of the Medicine. At the level of the Medicine Model, the determiner code is shown as either a kind or an instance, as different stages of a business process will require it to be identified at different levels. For example, if an ingredient must be specified in this way in a prescription for clinical use, it will be a kind, but that same ingredient, described in a reimbursement claim for supplying the preparation to that prescription may use an instance, and may need to state the lot number of the actual ingredient entity used.

The ingredient(s) should be described using a coded vocabulary, applying the same principles as the coded vocabulary for the Medicine. There is a Description attribute to support textual description of the ingredient if no coded description is available. There is also the facility to communicate the lot or batch number of the ingredient if this is required by the business process being communicated. [from Medication]

A chemical substance used as ingredient in medicines. [from SPL]

Design Comments: Used when the ingredient strength is expressed in terms of a reference substance, which is specified by the ingredient classCode ACTIR (active ingredient where strength is specified in terms of a reference drug.)

For example, it is customary for beta-adrenergic receptor inhibitors (beta-blockers, e.g., propranolol) to specify strengths in terms of the precise ingredient. This has led to variants of the same active moiety to be dosed in terms of the precise ingredient used when that active moiety first appeared on the market. For example, metoporolol tartrate was first, its strength was specified in terms of precise ingredient, and hence, for easier comparison of doses, the subsequent metoprolol succinate was specified in terms of equivalent metoprolol tartrate.

Design Comments: Links to the molecule or ion that is responsible for the intended pharmacological action of the drug substance. Note that if a molecule (e.g., salt) dissociates into moieties (ions) where each ions could be considered responsible for the (potentially different) pharmacological action of the drug, one should use multiple activeMoieties, one for each ion. [from SPL]

Design Comments: The molecule or ion that is responsible for the intended pharmacological action of the drug substance, excluding those appended or associated parts of the molecule that make the molecule an ester, salt (including a salt with hydrogen or coordination bonds), or other noncovalent derivative (such as a complex, chelate, or clathrate).

Examples: heparin-sodium and heparin-potassium have the same active moiety, heparin; the active moiety of morphine-hydrochloride is morphine.