Metoclopramide suppositories

Metoclopramide hydrochloride controlled release suppositories were prepared by mixing Witepsol W35 with 30 % lecithin [13]. The metoclopramide is incorporated in this base in a (solid) reversed micellar solution. The diffusion rate of the active substance from the melted suppository in contact with the aqueous rectum fluid was very low. Compared to licensed normal metoclopramide suppositories a five times longer mean residence time was found in vivo for the lecithin suppositories. 

Rectal administration For outpatient treatment when oral dosing is not possible, suppositories containing 25 mg metoclopramide have been extemporaneously compounded (5 pulverized oral tablets in polyethylene glycol). Administer 1 suppository 30 to 60 minutes before each meal and at bedtime. 

An example from pharmaceutical quahty control can serve as a model here. In the analysis of suppositories, the matrix components (e.g. wax) are displaced by a nonpolar solvent for a few centimeters beyond the solvent front of the subsequent chromatography of the substance, and this can then proceed through the matrix without further problems. Figure 65 shows the chromatogram of GastrosU suppositories (active substance metoclopramide base) after derivatization in an iodine chamber. The matrix components are clearly visible in the upper part of the plate. 

Example Metoclopramide base from Gastrosil suppositories. The first solvent system, which is polar, displaces the suppository mass beyond the later solvent front of the main TLC run. 

Figure 87. Identification of metoclopramide base and polidocanol in a suppository mass after dipping in a modified Dragendorff reagent...

Lane 1 metoclopramide base, lane 2 polydocanol, lane 3 witepsol (suppository base), lane 4 suppository (dipping height is not the SS front)... 

Migraine headaches accompanied with nausea and vomiting can be controlled by starting with a prokinetic such as metoclopramide or domperidone in a suppository, followed by an analgesic in a second suppository. 

Schneeweis A, Miiller-Goymann CC (2000) Controlled release of solid-reversed-micellar-solution (SRMS) suppositories containing metoclopramide-HCl. Int J Pharm 196 193-196... 

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