Stability tests on 12 vitamin C formulations at 80°, 60°, and 55° showed the failure of Arrhenius' Law in heterogeneous solid systems.The tablets contained 50 mg. ascorbic acid, 1 mg. Mg stearate (lubricant), and 149 mg. excipient and agglutinant.Lactose was recommended (followed by mannitol, sucrose, and starch, the last not advisable) as excipient with poly(vinylpyrrolidinone) (4 mg./tablet) as agglutinant.24 references.