Typically insulin does not cause those type of problems. Make sure his doctor knows. Good Luck!My boyfriend was recently diagnosed with Type 1 diabetes. He's fit, and before the onset of his diabetes symptoms, was very healthy. Once he started on insulin, he immediately started feeling better. However, just a couple of weeks later, muscle pain set in and has gotten increasingly worse. He can't sleep for more than an hour and a half at a time, and he's plainly in agony. It affects his arms and legs and pectoral muscles. It's not the tingling nerve pain I've read about - it's more of a deep, throbbing muscle pain. Has anyone else had symptoms like this or know what could be causing them? His doctor has prescribed muscle relaxants and Vicodin, but even doubling up on doses does not affect the pain or allow him to sleep through it. Thank you!