Places looked: Wikipedia, PubMed, DrugDigest
What I'm looking for:
I need a poison or drug that can be used to slowly kill someone over time - a couple of weeks to a month tops. Something that in low doses isn't going to do much/any damage, but would likely show up in blood tests (murderer is drugging self and others to throw off police). Also something that is either linked to some sort of chemical/biological/medical research and/or normally found in a lab.
Props if it is used in more than one field of research.
Several groups of researchers are competing for the same grant. One researcher is also in the process of murdering his colleagues involved in his project. He wants to do it in a manner that suggests that someone they're competing with is behind it. As a result, he also doses himself and some people from some of the other projects - but without any intention of killing them/himself. No one from the group being framed will be dosed. I'd like to use something that would initially lead the cops to the group being framed, but once they're cleared could eventually be linked back to the actual murderer.
My original plan had been to use a tyrosine kinase inhibitor because the articles I've found at PubMed suggest that it can cause congestive heart failure in large doses (and used in both cancer and diabetes research, but appears to be more common in cancer research). However, it can apparently take a really long time (mean 169 days) and I'm not certain if it'd be fatal (or if the symptons would have the victims going to the doctor and figure out what's going on). And it probably requires some preexisting conditions.
That said, DrugDigest lists grapefruit juice (and things including grapefruit juice) as something you Do Not Touch while taking, so I'm wondering if that could cause another reaction of some sort/kill the people? (Say, the person responsible has been slipping them the Sunitinib and stocks the fridge with Mountain Dew.) Or does grapefruit juice just not make it work? Another option is a brand new, not yet on the market inhibitor that causes heart failure more quickly that the other group happens to be in the process of developing (and the killer got his hands on somehow :/ ), which gives me more wiggle room but adds a few more problems.