What occurs if testosterone is abnormally high?

How high is high?: Reference range for testosterone depends upon lab, method used, gender & age. So how high is high? It's very unlikely for someone to have naturally high t. But excess t above upper limit of normal from too much gel, patch, shot, etc can lead to many side effects eg change in mood for worse, oily skin, acne, hair loss, prostate enlargement, increase risk of clotting thus heart attack & stroke.