IIG (Inactive Ingredient Guide Database) algorithm retrieves the largest value of each excipient for each route of administration and dosage form in FDA’s master database but does not reveal the formulation of any product.
The FDA Inactive Ingredient Database (IID) can be used to justify the safety of an excipient in a proposed formulation.
However, it's important to distinguish between Maximum Potency and Maximum Daily Intake (MDI) (also called Maximum Daily Exposure, MDE). FDA specifically states that Maximum Potency is not the same as Maximum Daily Intake unless the product is taken only once per day.
Maximum Potency currently shown in the IID comes from multiple approved products containing the excipient.
Maximum Potency in IID (P) = the highest amount of the excipient per dosage unit.
Maximum Daily Intake (MDI) also comes from multiple products containing the excipient but is based on a calculation of excipient exposure due to maximum daily dose (MDD). Since products that are dosed multiple times a day leading to a maximum daily exposure may not be the same as those products with the highest unit dose amount of the excipient.
MDI Calculation
Maximum Daily Intake (MDI) = Maximum Potency × Maximum Daily Dose (number of units/day)
Maximum Potency vs. Maximum Daily Exposure
As per FDA guidance,
The maximum potency currently shown in the IID comes from multiple approved products containing the excipient. It is the highest amount of the excipient per dosage unit.
Maximum daily exposure also comes from multiple products containing the excipient but is based on a calculation of excipient exposure due to maximum daily dose.
