In the statement published on his Instagram account Friday, Silva said he has always "played clean" and is still waiting for the "results and analysis from the specialists that are working to reveal the truth."
He said the rush to condemn him has been "unfair."
Silva was among the UFC fighters suspended this week after failed drug tests. He is waiting for results from his "B" samples.
The former middleweight champion beat Nick Diaz on Jan. 31 at UFC 183 in his return to the cage after breaking his left leg 13 months ago.
Silva started his statement by saying that what matters "now is the respect from those who have followed" his career.
"I don't know what to apologize for, because I am still waiting for the results and analysis from the specialists that are working to reveal the truth," Silva said. "Everything that I took since my injury are being analyzed. I look for the truth as much as all those who were surprised with the results. I always played clean, I was never a cheater."
The 39-year-old Brazilian said he would "never risk" jeopardizing a career that he "took so long to build."
"I think that the hurry some people have to condemn me is unfair," Silva said. "The time it takes to destroy a reputation is infinitely less than that is taken to build it. I want those who have always supported me to know that I am still fighting for all the sad happenings of this situation to be cleared."
Silva noted that during his 18-year career, he never failed any doping tests.
"In and out of the octagon, I never slipped in compliance with the principles that always guided me. With much honor and dignity, I defended my country wherever I fought," Silva said. "I never used any substances to better my performance in my fights."
Diaz and Hector Lombard were the other two high-profile fighters temporary suspended by UFC this week, prompting the world's leading MMA promotion to announce the launch of a multimillion-dollar anti-doping plan in which all fighters will be subject to random performance-enhancing drug testing beginning in July.
Former UFC Champ Silva Fails 2nd Drug Test
Brett Okamoto discusses Anderson Silva having failed a second drug test administered by the Nevada State Athletic Commission and if he will fight again in the UFC.