Medications might also cause a drop in blood pressure. Beta-blockers and nitroglycerin, used to treat heart disease, are common culprits. Diuretics, tricyclic antidepressants, and erectile dysfunction drugs can also cause hypotension. Some people have low blood pressure for unknown reasons.
Theoretically, then, the President can probably pardon him/her-self for any Federal crime â but this only prevents actual prosecution for that crime, not impeachment for the crime itself. Prior Answer, to the hypothetical of the VP murdering the President and then pardoning himself:
The U.S. Constitution gives the president almost limitless power to grant pardons to those convicted of federal crimes. While the president cannot pardon someone impeached by Congress, he or she can pardon anyone else without any Congressional involvement.