Hydroxocobalamin Base

Thompson J P, et al. Clinical Toxicology, 2012, 50(10), 875-885.

Hydroxocobalamin is a potent cyanide poisoning remedy because the cobalt compounds bind and detoxify cyanide.
· Pharmacokinetics and Pharmacodynamics
The pharmacokinetic data in dogs and humans show two-compartment model with first-order elimination kinetics for hydroxocobalamin. Pharmacodynamic studies in animals indicate that it could be used as a remedy for human cyanide poisoning.
· Efficacy in Human Poisoning
Limited evidence supports the sole efficacy of hydroxocobalamin in severe cyanide salt poisoning. Its effectiveness in smoke inhalation is confounded by the uncertain role of cyanide exposure in fires, potential effects of other chemicals, and the influence of concurrent therapeutic measures like hyperbaric oxygen. Evidence for its efficacy in pure hydrogen cyanide poisoning is absent; extrapolation from ingested cyanide salt poisoning may not be reliable. The rapid absorption of inhaled hydrogen cyanide may render the slow intravenous administration of hydroxocobalamin less effective in such cases.
· Adverse Effects
Both animal and human data suggest a low incidence of clinically significant adverse effects with hydroxocobalamin. However, one human volunteer study reported delayed, prolonged rashes in one-sixth of subjects who received 5 g or more of the drug, appearing 7 to 25 days post-administration. Rare adverse events have included dyspnea, facial edema, and urticaria.

Van der Kuy P H M, Merkus F, et al. Cephalalgia, 2002, 22(7), 513-519.

In this basic pilot study, the preventive effect of intranasal nitric oxide (NO) scavenger hydroxocobalamin on migraine was evaluated. This prospective, open-label study suggests that intranasal hydroxocobalamin (OHB12) as a NO scavenger may have a preventive effect on migraine.
· Evaluation methods
An open trial was conducted involving twenty patients, each with a history of migraine lasting less than one year and experiencing between two to eight migraine attacks monthly. The study included a baseline phase followed by a three-month treatment period during which participants received 1 mg of intranasal hydroxocobalamin daily.
· Results
Among the patients, 10 out of 19 exhibited a decrease in migraine attack frequency of 50% or more, representing 53% of the total participants (termed responders). In 63% of the patients, there was also a reduction of 30% or more. The overall mean attack frequency in the entire study group decreased from 4.7 ± 1.7 attacks per month to 2.7 ± 1.6 (P < 0.001). The migraine attacks among the responders fell from 5.2 ± 1.9 at baseline to 1.9 ± 1.3 per month (P 0.005) and in the non-responders by a significant amount, from 4.1 ± 1.4 to 3.7 ± 1.5 (P > 0.1). There was also a reduction in the total time of the monthly migraine attacks, migraine days, and acute-treatment medications taken per month.