Tease. 
Taking a couple of Tums before starting the donation will help alleviate that issue. They should have them there. I’m surprised that they didn’t offer them to you when you mentioned the tingling.
According to my pal Vlad–ZESTY.
I did some sort of “whizzing something out” and then putting the blood back in me. They told me things might tingle, but I don’t remember that they did. It was supposed to be for a kid with cancer, and they rung me up and told me he was better and I didn’t need to go again. I’m not sure that that was true 
I expect that people might feel more “hassled” now by reminders because of emails and sms where they can seem to rain down on you. When it was letter reminders, or phone calls, I think we’d only get them when they had really run short and needed people to show up.