Ca2+ channels can then be open for a longer time and allow greater acetylcholine release to stimulate muscle at the end plate. Pharmacokinetics
Amifampridine is quickly and almost completely (93–100%) absorbed from the gut. In a study with 91 healthy subjects, maximum amifampridine concentrations in blood plasma were reached after 0.6 (±0.25) hours when taken without food, or after 1.3 (±0.9) hours after a fatty meal, meaning that the speed of absorption varies widely. Biological half-life (2.5±0.7 hrs) and the area under the curve (AUC = 117±77 ng∙h/ml) also vary widely between subjects, but are nearly independent of food intake.The substance is deactivated by acetylation via N-acetyltransferases to the single metabolite 3-N-acetylamifampridine. Activity of these enzymes (primarily N-acetyltransferase 2) in different individuals seems to be primarily responsible for the mentioned differences in half-life and AUC: the latter is increased up to 9-fold in slow metabolizers as compared to fast metabolizers.Amifampridine is eliminated via the kidneys and urine to 74–81% as N-acetylamifampridine and to 19% in unchanged form. Chemistry
3,4-Diaminopyridine is a pale yellow to pale brown crystalline powder that melts at about 218–220 °C (424–428 °F) under decomposition. It is readily soluble in methanol, ethanol and hot water, but only slightly in diethyl ether. Solubility in water at 20 °C (68 °F) is 25 g/L. The drug formulation amifampridine phosphate contains the phosphate salt, more specifically 4-aminopyridine-3-ylammonium dihydrogen phosphate. This salt forms prismatic, monoclinic crystals (space group C2/c) and is readily soluble in water. The phosphate salt is stable, and does not require refrigeration.
Tobi may refer to:

Tobi (given name), a unisex name
Tobi (island), island in the Palauan state of Hatohobei
Tobian language, the language of Tobi
Hatohobei, an island and the southernmost of Palaus sixteen states
Tobi (month), in the Coptic calendar
Tobi!, a 2009 television series
Tobramycin, an antibiotic drug that is sold under the brand name "Tobi"
Tobi (Naruto), the alias of Obito Uchiha, one of the primary antagonists in the anime and manga series Naruto Shippuden
ToBI, a standard for transcribing English intonation
Tobi shokunin or tobi for short; construction workers in Japan
Tobi trousers, the typical piece of clothing of tobi shokunin
Texas Oilmans Bass Invitational (TOBI)
Tobi (1978 film)

See also
Tobias
Toby (disambiguation)