Could Purple Colored Rashes On Back Be Side Effect Of Claritin?

Last Friday I woke up unable to breath though my nose and I kept sneezing. As a result, I took liquid Claritin (the children's kind). The next day I noticed a few dark purple dots on my hip. Then the very next day I had even more purple dots on my left lower back and on my right lower back ("lovehandle" area). It looks like a rash and I didn't know if the medicine caused this or something else. I am 5'5, weigh 142 and I had a chrondrosarcoma tumor in my head but did radiation back in August 2010.