Pharmaceutics
Drug-Excipient Compatibility Predictor
Scores the risk of a chemical interaction between a drug's functional groups, your excipients and storage conditions.
Risk score
Select at least one drug functional group and one excipient to see the risk.
Formulation
Tap every group that applies. Each chip shows its risk and the points it adds.
Try an example
Drug functional groups
Pick at least one
Excipients
Pick at least one
Environmental factors
Optional
Score = Σ drug groups + Σ excipients + Σ conditions + interaction penalties
Drug functional groups and excipients add 3 (high risk), 2 (medium) or 1 (low). Environmental factors add 4 (high), 2 (medium) or 1 (low). Two specific interactions add a penalty: primary amine + lactose (Maillard reaction) +5, and ester + high pH (hydrolysis) +4.
≤ 5 low · compatible | 6–10 medium · caution | 11–15 high · caution | > 15 critical · incompatible
Formulation tips — for amine drugs, use mannitol instead of lactose; for ester drugs, maintain an acidic pH and use desiccants; for oxidation-prone drugs, add antioxidants and use a nitrogen blanket.
Common questions
Lactose is a reducing sugar. Its open-chain aldehyde reacts with primary amines in the Maillard reaction, giving brown discoloration and loss of drug — so the predictor adds a +5 penalty when both are selected. Mannitol, a non-reducing sugar alcohol, is the usual substitute.
No. The score is a screening heuristic built from a short list of groups and two known interactions. Confirm any formulation with binary drug–excipient mixtures under accelerated conditions (40°C / 75% RH), monitored by DSC, FTIR and HPLC.
High temperature, humidity, extreme pH and metal ions accelerate almost every degradation pathway at once, so a high-risk condition adds 4 points against 3 for a high-risk group.
Yes. Every reactive group adds its own points, and the recommendations (for example, an antioxidant for amines, aldehydes and thiols) depend on which groups are present.
Prepared by the PharmaWallah student team. Verify results with your textbook or instructor. Report an error · Editorial policy