I took part in clinical studies once & very nearly ended up being admitted as an in-patient because I had such a bad reaction. The drug in question -Becotide had at that time been used for a long time but what I was being subjected to was nebulisers with the drug being diluted in various substances e.g. water & saline.
Young & naive I figured that a little saline or water couldn't do much harm & I'd used the drug before so what could go wrong? The doctor conducting the trial didn't know which he was giving me. After the panic was over & I'd been given drugs to reverse the problem, he told me that he thought the reaction had been caused by the Becotide diluted with water.
Older & wiser I'd now be very cautious about taking part in any clinical trials after that experience!
Lidia