Doxycycline Hyclate and doxycyclene

I've been on Doxycyclene for 2 weeks now. I was trying to get rid of my acne. I've vomited twice. (The likelihood of this increases when there's very little food in the tum)Before I vomited, I'd feel like I was having a heart attack. A sudden tightness in the chest, breathing became difficult, a depression that felt like the end of the world. All eventually leading up to vomiting. My acne hasn't witnessed much improvement either. Either it doesn't suit me or I haven't been taking it properly.

My significant other took Doxycylene, 100 mg, twice a day for two weeks to treat a swollen lymph node under his arm. During the treatment he experienced nausea, stomach pain, rash and cold sweats, nothing too bad. 3 days after the last dose everything got significantly worse. It started with sever chest pain, so bad we went to the emergency room thinking it was a heart attack or blood clot. They found nothing and discharged him. Over the next 3 weeks he started vomitting, diahrea and developed jaundice. Constant queeziness and chest pain. After numerous tests, ultra sounds, MRCP, the doctor has ruled out various hepatitas's and every other disease he could think of. He's also rulled out any kind of bile duct blockage after the MRCP. Its now been 7 weeks since all this started, my friend has dropped 40 lb's (190 down to 152) and still dropping. Our doctor (gastro interologist) has admitted he's stumped and is currently contacting a professor in Miami as a last hope. The only thing our doctor keeps comming back to is the Doxycyclene and that my friend may have had that one rare acute reaction. We're frazzled and don't know what to do next.