I’ve had headaches for the past month. Today I took a BC powder (aspirin) after about 3 hours I got a random back spasm, from my chest all the way to my butt bone. After it ended I was feeling disoriented and lightheaded.
Hello and welcome to the forum. Sorry you have had a persistent headache and then this reaction after takign BC powder. Neither thing you mention are common side effects. Here's a full list of potential side effects. https://www.webmd.com/drugs/2/drug-15323/bc-headache-powder-oral/details/list-sideeffects People do occasionally get some anxiety symptoms and perhaps this is the disoriented sensation you describe. The back spasm is also not a common finding. Muscle tremors is listed but that is the closest thing I could find. This may have been a fluke. Being disoriented and light headed are not common but are listed in the literature. It sounds like this type of aspirin did not really work well for you.