Risperidone preparations

Risperidone (11) was prepared starting from 3-(2-chloroethyl) 180, via 3-(2-aminoethyl) 181, and 3- 2-[4-(2,4-difluorobenzoyl)piperidino]ethyl 182 derivatives of 4//-pyrido[l, 2-rz]-pyrimidin-4-ones as depicted in Scheme 11 (94MIP8, 95MIP7). 

Risperidone 458a was prepared starting from the 3-(2-chloroethyl) compound 483, via 3-(2-aminoethyl) 484, and... 

Raman often is evaluated as an alternative to an existing high performance liquid chromatography (HPLC) method because of its potential to be noninvasive, fast, simple to perform, and solvent-free. Raman was compared to HPLC for the determination of ticlopidine-hydrochloride (TCL) [43], risperidone [44] in film-coated tablets, and medroxyprogesterone acetate (MPA) in 150-mg/mL suspensions (DepoProvera, Pfizer) [45] it was found to have numerous advantages and performance suitable to replace HPLC. In an off-line laboratory study, the relative standard deviation of the measurement of the composition of powder mixtures of two sulfonamides, sulfathiazole and sulfanilamide, was reduced from 10-20% to less than 4% by employing a reusable, easily prepared rotating sample cell [46]. 

For patients with chronic psychotic symptoms who do not comply with a daily medication regimen, a long-acting depot preparation should be considered after stabilization with oral medication. Fluphenazine, haloperidol, and risperidone are the only long-acting injectable antipsychotic medications currently available in the United States. 

A group from Spain patented a similar synthesis of risperidone (1) using similar synthetic transformations but in a different sequence (Scheme 2). Reaction of 2-aminopyridine with 2-acetylbutyrolactone in polyphosphoric acid at 160 °C afforded alcohol 15, which was hydrogenated to 16 and then converted to chloride 10 with thionyl chloride. Benzoyl piperidine 19 was prepared in a similar manner as in Scheme 1. In contrast to Scheme 1, 19 was alkylated with 10 prior to conversion to the 1,2-... 

Arnold [1] prepared the hydrophilic and bioabsorbable copolyester, poly (monostearoyl glycerol-co-succinate) (1), which was used in the sustained release of Risperidone . 

I Liquid preparations (e.g. risperidone, fluoxetine) and oral dispersible tablets (e.g. olanzapine, risperidone, mirtazapine) are aimed at ensuring administration/improving compliance. They generally have minimal effects on absorption. 

It is important to simplify the treatment regimen and to ensure that the patient is receiving the drug. In cases of suspected severe and dangerous noncompliance or with failure of oral treatment, the patient can be treated with injections of fluphenazine decanoate, haloperidol decanoate, or other long-acting preparations, including risperidone microspheres. 

Silva A, Gonzalez-Mira E, Garcia M, Egea M, Fonseca J, Silva R et al. Preparation, characterization and biocompatibility studies on risperidone-loaded solid lipid nanoparticles (SEN) High pressure homogenization versus ultrasound. Colloids and Surfaces B Biointerfaces. 2011 86(1) 158-165. 

Risperidone free base preparations include film-coated tablets (1, 2, 3, 4 and 6 mg), orodispersible tablets (0.5, 1, 2, 3 and 4 mg), liquids at 1 mg/mL and depot preparations. Paliperidone is available as free base tablets (3, 6 and 9 mg), the hexadecanoate (palmitate) and extended release formulation using an osmotic-controlled release oral delivery system. 

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