I have intermittently come across concerns on this site regarding the supply and thermal/photo stability of saline solutions of methyl cobalamin.
Since I wanted to source a saline solution myself I thought the following information would be of general interest.
1. Having been unimpressed by sourcing in the UK I approached Arnika in Germany and found that they will take an order in English by email without any registration by way of this email address. Payment was made via email/Paypal. Delivery was a few days.
Manufaktur@arnika-apo.de
Service was excellent
2. After much literature searching the following reference allayed my concerns regarding storage of the ampoules
researchgate.net/publicatio...
Stability of high-dose methylcobalamin injection
Article in Journal of Applied Therapeutic Research 6(3):15-18 · January 2008 with 665 Reads
• C. Kusadome
• Y. Shibayama
• Y. Nishi
• Yasuo Takeda
◦ 36.97
◦ Kagoshima University
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Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease. It is treated with an active form of vitamin B12, methylcobalamin (mecobalamin). Recently, it has been reported that high-dose treatment with methylcobalamin may delay the progression of ALS. We have manufactured high-dose injections of methylcobalamin as a hospital formulation; however, the stability of the injection was unclear. Here we examined the stability of the injection using high performance liquid chromatography (HPLC). Methylcobalamin solution (12.5mg/ml, diluted with saline) was sealed in a brown glass ampoule under dark conditions (1-2 lux). The ampoules were sterilized by autoclaving (115°C, 30 minutes), and then protected from light with aluminum foil. After the ampoules had been kept under cool conditions (4°C) for 3 months, the concentration of methylcobalamin was found to be 96.4 ± 2.4% (mean ± S.E.) of the control value. After 6 months, methylcobalamin had decreased to 91.6 ± 1.4% (mean ± S.E.). In contrast, methylcobalamin quickly degenerated to 49.9 ± 8.2% (mean ± S.E.) of the control after only four hours' exposure to bright light (1,000 lux). In conclusion, the results suggest that injections of high-dose methylcobalamin can endure an autoclave, but methylcobalamin rapidly deteriorates with exposure to light. Thus, high-dose methylcobalamin injections should be prepared under dark conditions to prevent light-dependent degeneration.