There's a weird thing that some people with LC have where large blood draws lead to symptom relief for hours/days/weeks. Probably something something microclots or inflammatory something being removed temporarily, or maybe the body's response to injury...? No one knows, we're all just speculating. But it happened to me personally after a big blood test and then I was seriously looking into donating blood regularly, or, alternatively, nurturing a crop of medicinal leeches at home.