I m not sure if I m having a reaction to Zantac and also yesterday to nexium. It seemed I had the majority of the side effects to nexium so I switched to Zantac. Feel like I have pins and needles inside of me. I was fine u til 3:00 today on it but then I started feeling funny. I am very exhausted suddenly as well with the chills and prickly feeling from this. Nexium reaction was worse yesterday. Can I be having a reaction to this? Maybe an allergic one? I m not struggling to breath, but feel like my body is fighting something like a reaction. I haven t taken anything today except this. I ve eaten nothing different.