I have a tube of retin a that has a date 4/2012. Today is 7/2014. Does it lose its effectiveness over time?

After the expiration date most medications will lose some of their potency.  It would not be dangerous to use but may not be as effective. 

Dear
Sunnielyons,



Yes,
Retin-A will lose its potency over time. Some medicines such as tetracycline
type antibiotics can actually be quite dangerous to take after expiration date.
I am not aware of any danger with older Retin-A other than the fact it will not
be as effective. Two years seems like the shelf life has been exceeded.



I
hope this has been helpful.



Robert
D. Wilcox, M.D.

All medication will either lose efficacy over time and/or completely alter. Some medication (not Retin-A) can even become poisonous if taken too far after the expiration date. For Retin-A, yes, it has lost efficacy, which means now when you get a new tube and use it, you will need to be cautious because you will be used to using a much lower potency product. Toss your tube and get a new one. That isn't good to use. "This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."