To much potassium kills. Certain diuretics are potassium sparing so if you have this in your system if you collapse and the Medics give you the drip overdose some potassium which in turn will stop your heart. Happed in sport a few times. Ie bodybuilding and people making weight. You can also over dose on it by eating to many bananas. Happened to Peter Andre the singer.

Caffeine is the biggest issue for high blood pressure I'm in the minds of trials and researching it.