Linda, Any cortef made since aprroximately Spring '98 has been made with a different formulation than the old cortef. Upjohn is using a new suspending agent since that time. So the lot number is not as significant as the fact that there is a white sediment. The sediment does in fact contain hydrocortisone and if it is not completely shaken back into suspension, the potency of the liquid cortef is compromised. Therefore your child could be getting undermedicated. If you can shake it vigorously from side to side in a rocking motion , you may be successful at resuspending the sediment. As long as the sediment is re- suspended you should be fine. I personally was never able to accomplish that so we switched to pills. Since then we have had excellent 17OHP results. Upjohn is well aware of the problem and is changing the labelling on the BOTTLE, BOX AND PRODUCT INSERT to include specific directions about the shaking process. To date they are not talking about changing the formulation to eliminate the problem. They are simply changing the labelling, probably effective in March or April, so I am told. Personally I do not think this alone will solve the problem. I believe they need to re-educate the pharmacists and consumers in a more direct way. It's probably been atleast a year or so that they have been aware of this problem. I have been talking with Upjohn for about 9 months regarding this problem. Things don't move too quickly in the corporate world and as I have said to them children's health is being compromised due to corporate complacency. If I can provide any more info please e-mail me directly. Good luck concerned mom