In his second season with the Padres, Cameron hit just .242 and struck out 160 times while belting 21 homers.
"After all of the analysis and testing, I can only conclude that a nutritional supplement I was taking was tainted," Cameron said in a statement. "Unfortunately, the actual supplement is gone, and therefore cannot be tested. Without the actual supplement in hand, the rules are clear, and I must accept the suspension."
"Mike has been a valuable member of the Padres over the last two seasons who has been respected for his contributions on the field, his stature in the clubhouse and his involvement in the San Diego community," Padres CEO Sandy Alderson said in a statement.
"Accordingly, the Padres are extremely disappointed that Mike has tested positive for a stimulant banned by MLB's drug policy. Nonetheless, the Padres staunchly support that policy and hope that Mike's suspension serves as a reminder that performance enhancing drugs have no place in professional sports."