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:
Bill Clinton runs for Arkansas Attorney General (1976), while a fugitive from justice. Bill Clinton receives pardon on January 21, 1977, from President James Earl Carter. Bill Clinton becomes the FIRST PARDONED FEDERAL FELON ever to serve as President of the United States. All these facts come from Freedom of Information requests, public laws, and various books that have been published, and have not been refuted by Clinton.