Shares for DexCom Inc., a San Diego maker of blood glucose monitors, shot up 21 percent after the company posted its second quarter earnings.

DexCom (Nasdaq: DXCM) shares for the $1.88 billion market cap company were trading at $26.66 at market close Aug 8, up $4.68 for the day.

Second quarter net loss narrowed to $10.1 million in the quarter ending June 30, down from a net loss of $14.7 million in the like quarter of the previous year.

Total revenue increased to $35.8 million for the quarter, beating analyst projections of $31.1 million. Total revenue was $23.4 million in the like quarter last year.

— Meghana Keshavan