Allergic to Propranolol

Hello, I have been taking propranolol for about 6 months, usually just one tablet per day. However, a few days ago I took 2 tablets 12 hours apart and became very itchy and had the worst orange diarrhea I have ever experienced. I kept trying to figure out what I had eaten that was orange, and then it dawned on me that the tablets are orange. It was then that I read on the NIH website that propranolol can cause diarrhea in older populations. I am 61. The neurologist, who I really like, wrote to me that my reaction was an unusual one, so I sent him the link. Now it has been suggested I just stick to one tablet as opposed to two, however I don't want to take it anymore because of the extent of itching and diarrhea.
Coincidentally, my PCP recently wanted me to begin taking methadone again because the Norco is not controlling my sciatic pain and pain coming from my sacral spine. After taking a 5mg tablet I developed the worst case of hives I have ever had. Another allergic reaction. It is my understanding that sometimes those with certain kinds of medical problems can be more prone to medication allergies, and I wonder if anyone else has experienced anything like I have. Does anyone else have a suggestion for headache medication. I have used Nurtec with success, but after filling it twice, I fell into the Medicare "donut hole" and my copay went up 300 percent. My neurologist does give me some samples, but only 4 at a time.