NEW YORK — It shouldn’t surprise people too much, but pills to treat male impotence tend to see big increases in prescriptions around Valentine’s Day, according to published reports.

Bloomberg reported that prescriptions of such drugs as Pfizer’s Viagra (sildenafil) and Eli Lilly’s Cialis (tadalafil) are at their highest in the days leading up to the holiday.

According to Pfizer financial data, U.S. sales of Viagra were $253 million in first quarter 2010, compared with $234 million in the second quarter and $242 million in the third quarter, though the fourth quarter also saw a large increase in sales to $263 million.