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:
Of course the President can pardon himself. He is, after all, the executive, part of whose constitutional duty under Article 2 is to bring prosecutions and punish the guilty. You can't jail the head jailer, and you can't prosecute the head prosecutor's boss, unless he allows it.