Peruvian Customs sometimes have an issue with imported vitamin pills, fish oil capsules etc etc...and can request/demand that the receiver shows a prescription, or there is a prescription with the goods, made in the name of the receiver, before they will release the package....and even maybe request "duty"or tax to be paid.
If that is not done, they may return to sender.
You could try an inexpensive shipment and get your friend in the States to send it via USPS First Class International mail....that works for me, here in Peru, when I buy stuff off Ebay....nothing gone missing (yet) and the Serpost postie here will get a signature and ID number from the receiver.
Alternatively, buy local in Peru from a Natural Products outlet
Cheers, hope this helps...even thought it is a bit negative....voice of experience .