Originally Posted by Crazyforinfo
This isn't advice. My doctor said in his experience, people with low bp also have a spike from like climbing the stairs(light activity). Maybe this is the case. Have you ever taken your bp when drinking? (FYI I am on Beta Blockers for migraines which is how this convo came up).
Mine spikes, but because my bp is so low to begin with I don't reach normal (aside from the time I reacted badly to a medication and it spiked to 172/70, but that only lasted a few minutes - long enough to spook a nurse in the ER
A little about the autonomic nervous system, and how those with low bp can get spikes.
When your blood pressure is low your other organs may occasionally not get enough blood. Such as that woozy or light headed feeling when you're brain isn't getting enough. This triggers your ANS to send out signals to your body to release more catecholamines. Adrenaline to speed up your heart and constrict blood vessels, and norepinephrine (noradrenaline) to constrict peripheral vessels (in arms and legs). If your body keeps pumping these out your blood pressure will rise, the biggest change being on the systolic. Once they clear things settle down again.
Stress, any sort of stress - happiness, upset, fear, standing up, etc can trigger that adrenaline release as well.
If you add alcohol, a central nervous system depressant, into the mix it messes things up. For one, it acts as a vasodilator, meaning it can make blood pressure fall - which ones body would have to try harder to correct, and with that more epinephrine (adrenaline).
There's more to it than that, but that's the very basic. I wouldn't be surprised to learn that the BB, which also affects the CNS (why they help migraines) plus the alcohol doing the same thing was part of the problem. Less sensitive people may not notice it, or maybe most wouldn't notice it most of the time unless something, like blood volume, is a bit off.
... Which is why I won't touch any alcohol with a ten foot pool. My ANS is messed up, so there's no way I'm going to borrow more trouble.