Galantamine is used for the treatment of cognitive decline in mild to moderate Alzheimers disease and various other memory impairments. It is an alkaloid that has been isolated from the bulbs and flowers of Galanthus nivalis (Common snowdrop), Galanthus caucasicus (Caucasian snowdrop), Galanthus woronowii (Voronovs snowdrop), and some other members of the family Amaryllidaceae, such as Narcissus (daffodil), Leucojum aestivum (snowflake), and Lycoris including Lycoris radiata (red spider lily). It can also be produced synthetically. Studies of usage in modern medicine began in the Soviet Union in the 1950s. Galantamine was isolated for the first time from bulbs of Galanthus nivalis (common snowdrop) by the Bulgarian chemist D. Paskov and his team in 1956. The active ingredient was extracted, identified, and studied, in particular in relation to its acetylcholinesterase (AChE)-inhibiting properties. The first industrial process was developed in 1959. However, it was not until the 1990s when full-scale synthesis was upscaled and optimized.Since the alkaloid was isolated from a botanical source, it only had contents around 0.1%, which caused the yield to also be extremely low—in the single digits. Uses in mythology
In Homers Odyssey the god Hermes gives Odysseus a herb with "a black root, but milklike flower" called "moly", which Hermes claims will make Odysseus immune to the sorceress Circes drugs. It is believed that moly is the snowdrop Galanthus nivalis, which is a source of galantamine. The descriptions of moly given by Greek physician and herbalist Dioscorides support molys identity as Galanthus nivalis.
Galantamines competitive inhibition of acetylcholinesterase and allosteric nicotinic modulation serves as a dual mechanism of action.To reduce the prevalence of negative side effects associated with galantamine, such as nausea and vomiting, a dose-escalation scheme may be used. The use of a dose-escalation scheme has been well accepted in countries where galantamine is used. A dose-escalation scheme for Alzheimers treatment involves a recommended starting dosage of 4 mg galantamine tablets given twice a day (8 mg/day). After a minimum of 4 weeks, the dosage may then be increased to 8 mg given twice a day (16 mg/day). After a minimum of 4 weeks at 16 mg/day, the treatment may be increased to 12 mg given twice a day (24 mg/day). Dosage increases are based upon the assessment of clinical benefit as well as tolerability of the previous dosage. If treatment is interrupted for more than three days, the process is usually restarted, beginning at the starting dosage, and re-escalating to the current dose. It has been found that a dosage between 16–24 mg/day is the optimal dosage. Available forms
The product is supplied in prescription form only in twice-a-day tablets, in once-a-day extended-release capsules, and in oral solution. Side effects
Galantamines side effect profile was similar to that of other cholinesterase inhibitors, with gastrointestinal symptoms being the most notable and most commonly observed. One study reports higher proportions of patients treated with galantamine experiencing nausea and vomiting as opposed to the placebo group.