The US women's soccer team goalkeeper was found to have the diuretic Canrenone in her system when administered a urine test on June 15 by the US Anti-Doping Agency, reports NBC.
Solo has accepted a public warning for the infraction and will be able to compete in the London Olympics later this month as planned.
"I took a medication prescribed by my personal doctor for pre-menstrual purposes that I did not know contained a diuretic," Solo explained in a statement released Monday (July 9).
"Once informed of this fact, I immediately cooperated with USADA and shared with them everything they needed to properly conclude that I made an honest mistake, and that the medication did not enhance my performance in any way."
Solo continued: "As someone who believes in clean sport, I am glad to have worked with USADA to resolve this matter and I look forward to representing my country at the 2012 Olympic Games in London."
US Soccer also spoke out in support of Solo, insisting that she had not purposely broken any rules.
"After discussions with Hope, we fully support her clarification that the positive test for Canrenone was due to the use of a prescribed medication from a personal doctor for pre-menstrual purposes and not related to performance enhancement in any way," the organisation explained.
Solo recently competed in the ABC competition Dancing with the Stars.