Do you have Verizon by any chance?  I get calls from this number as well as about 20 other telemarketers or whatever.  I never had this problem until I got a verizon business line.

The number is usually unknown, but today came up 1-981-131-3485.  They always ask for Daniel and say they are the Pharmacy.  The people have been asked for over three years to stop calling, but they continue.  Sometimes they get perverted.  These people are obviously not from America and if they are are prime examples of those that should be sent back!!