Retake any classes where you scored a low grade. You may think that even one D on your transcript won’t matter, but medical schools look at the whole picture. You can explain what happened, but you’ll have better luck if you retake that class and have a better record on your academic transcript.
Study for the MCAT and take the test multiple times to get a higher score. Medical schools place a lot of importance on test scores, and sometimes this is the most important thing. If you get extremely high scores on the test but have some bad grades, admissions officers may be willing to overlook that simply to get a bright mind into their schools.
Check out the Best Foreign Medical Schools website (see Resources below). There are a number of practicing doctors who had problems getting into a medical school in the U.S. They attended schools in a foreign location for a year or two and then transferred back to a school in this country.
Spend at least a year in a graduate degree program and even consider finishing that degree. Medical schools are highly competitive, and they want students who will finish the program and go on to have lasting careers. If you can show that you can buckle down and get good grades in a higher learning program, the school may reconsider.
Write an excellent essay as part of your med school application. In this essay include why you got the poor grades, and make sure the school knows how important becoming a doctor is to you. If you have a rough year because your father died and you had to move home, tell them. These schools are more understanding than you might give them credit for.