Does anyone else have a problem with their throat, or voice when jabs are due? My daughter is a singer and finds that by about week 7, or leading up to week 7 after having had her b12 jab, her voice is beginning to sound a little rough and hurts or is sore. She also has less stamina to sing and general muscle fatigue. Had her vocal cords and throat checked so there is not actual problem there, but it happens regular as clockwork just before injection due. At moment she has them 7-8 weeks...except that doctor said her levels are up and would be good to stop for 3-6 months to see what happens. Huh! Husband said "Over my dead body". 7 weeks not enough though really.