Verkkothe white valacyclovir pill typically comes in strengths of 500mg and 1000mg, while the blue pill is often a lower dose for maintenance therapy. This blue and white round pill with imprint l837 on it has been identified as: Pain relief pm extra strength acetaminophen 500 mg /. Verkkopill identifier results for blue & white and round. Search by imprint, shape, color or drug name.