Chloroquine phosphate tablets

Table 3 gives a summary of the known dissolution problems with sugar-coated tablets. The progressive decrease in disintegration and dissolution has been ascribed to adherence of gelatin subcoat to the tablet core. This was also a conclusion made in a study where most of the core tablets were found to be dry even at the end of the dissolution test. " Fig. 9 shows an example of sugar-coated chloroquine phosphate tablets exposed to 40°C and 75% RH. Clearly, the dissolution rate decreases with time. ... 

P.I. Franklin-Ude, M.O. Emeje and S.l. Ofoefule, Evaluation of gellan gum as a granulating agent for chloroquine phosphate tablets, J. Pharmacol. Toxicol, 3 53-63,2008. 

Cheng et al. reported the use of a synchronous fluorimetric method for the determination of primaquine in two-component antimalarial tablets [31]. Ground tablets were dissolved in water and the mixture was filtered. The fluorescence intensities of chloroquine phosphate and primaquine phosphate, in the filtrate, were measured at 380 nm (excitation at 355 nm) and 505 nm (excitation at 480 nm), respectively. The calibration graphs were linear from 1 to 8 pg/mL of chloroquine phosphate and 10 to 110 pg/mL of primaquine phosphate. The mean recoveries were 98.2-101.49% and the relative standard deviations were 2.23%. 

Fig. 9 Release of chloroquine phosphate from marketed sugar-coated tablets on storage at 40°C and 75% RH up to 20 day. Evidently, the dissolution rate falls with increase of the duration of storage under accelerated conditions of temperature and humidity.

Chloroquine has a bitter taste, which can deter children from taking it, so a sweet effervescent formulation of chloroquine phosphate has been compared with chloroquine tablets in a pharmacodynamic study (37). However,... 

Yanze MF, Duru C, Jacob M, Bastide JM, Lankeuh M. Rapid therapeutic response onset of a new pharmaceutical form of chloroquine phosphate 300 mg effervescent tablets. Trop Med Int Health 2001 6(3) 196-201. 

Otioroquine and Chloroquine Phosphate. Chlor-oquine (Aralen HCI) can be considered the prototypical struclure lhal succeeded quinine and came into use in the mid-1940s. The phosphate salt (Aralen Phosphate) is used in oral dosage forms (tablets), and ihe hydrochloride. sail is administered parenierally. Until recently, chloroquine was... 

Chloroquine phosphate (aralen) is available in 250- and 500-mg tablets (equivalent to 150 and 300 mg base, respectively) for oral administration. The adult dosage is two 500-mg tablets immediately, followed by one 500-mg tablet at 6, 24, and 48 hours. Tlie dosage for children is... 

A simple, sensitive, and selective method for the determination of amodiaquine hydrochloride in tablets has been developed. It is based on a color reaction with chloramine-T in the pH range 7.4- 8.0. The chromogen is extracted with chloroform and the absorbance is measured at 442 nm. Beer s law is obeyed in the concentration range 1-200 n%/. The coefficient of variation has been found to be 0.64% and the recovery ranges between 100.3 and 102.5%. Chloroquine phosphate or primaquine phosphate do not interfere with the method (29). 

There have been 2 recent reports of acute porphyria developing following ingestion of chloroquine. In one case (8 -) an elderly patient treated for cutaneous porphyria tarda received 10 times the prescribed dose and suffered a severe, acute porphyric crisis as a result. The other report (9 -) referred to a 39-year-old woman who developed acute porphyria after a single dose of a combination chloroquine-primaquine tablet for malaria prophylaxis. The dose of chloroquine phosphate ingested by this patient was 300 mg. 

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