Hello,

Many of your pharmacy creams, ointments, including lansinoh and purelan
lanolin have experation dates.  The reason for lanolin is because it can
become rancid causing foul smell and taste.  As far as having to throw away
because it is "rotten", no.  I would not use it on nipples, but I personally
use it on my dry hands and feet (my husband hates it).  It will not cause
harm, but it will have a very offensive smell and ordor with time.

Pat Bull, RN, IBCLC
The Breastfeeding Connection/Medela
Naperville, IL