I Had A Sev Ere Reaction In Taking Three Drugs:

I had a sev ere reaction in taking three drugs: Ranctidine, Promethazine and meclizine. One was for heart burn, one was for nausea and one was because I had some dizzy episodes. I became incoherent, could not walk well, was totally doped up and out of it. My internist told me to take these. I have stopped and the reaction stopped the next day. Do these drugs interact?