Quinidine sulphate

Quinidine sulphate 0.4 g Crystal violet Each ml of 0.1 N HC104 e= 0.02490 g of (c20h24n2o2)2.h2so4... 

After single oral doses of 4.5 mg/kg of quinidine sulphate to 10 subjects, peak plasma concentrations of 0.9 to 1.8 xg/ml (mean 1.2) were attained in about 50 minutes (T. W. Guentert et al., J. Pharmacokinet. Biopharm., 1979, 7,315-330). 

Quinidine Sulphate Amidephrine Mesylate Pipoxolan Hydrochloride Polythiazide Amodiaquine Guanoclor Sulphate Methyl Benzoquate Nalorphine Oxyclozanide Bamipine Hydrochloride Albendazole Chlormadinone Acetate Sulphamethizole Buprenorphine Fludrocortisone Acetate Hydroxyephedrine Hydrochloride Lormetazepam Sulphamethoxydiazine Bialamicol Hydrochloride Bunamidine Hydrochloride Hordenine Sulphate (dried) Mesterolone Carbidopa... 

Midha and Charette carried out quantitative determinations of quinidine in plasma and whole blood. Cinchonidine was added to the plasma sample to be analyzed as an internal standard. The alkaloids were extracted with benzene at pH 12.0. The residue from the extract was mixed with 25 yl of trimethylanilinium hydroxide in methanol, and aliquots (1-2 ul) were injected into the gas chromatograph in which the injection port was held at 350°C. The methyl derivatives of quinidine and the internal standard gave well separated symmetrical peaks. Detection by flame ionization gave a linear response over the range 0.2-12.0 vg quinidine/ml plasma. The limit of detectability was 0.05 ug/ml and the method was adequate for following blood profiles of 200 mg quinidine sulphate doses in humans. The recovery of quinidine... 

Quinidine sulphate may also be prepared from the mother liquors remaining after separation of quinine from the extracts of Cinchona by a known process. 

Class I anti-arrhythmic drugs normally prolong the refraetory period of cardiac muscle, re-duee its exeitability, and above all minimise the eonduetion veloeity for example, quinidine sulphate, disopyramide phosphate, toeainide hydrochloride, proeainamide hydroehloride, mexiletine hydrochloride, aprindine, ete. 

MoustafaMA, Al-ShoraBI, Gaberl t Gouda MW. Decreased bioavailability of quinidine sulphate due to interactions with adsorbent antacids and antidimhoeal mixtures. IntJ Pharmaceutics ( 9S7) 34, 207-11. 

A further study in 12 healthy subjects found that the AUC of a single 200-mg oral dose of quinidine sulphate was increased by 16% by nifedipine 20 mg. The quinidine clearance was reduced by 14% and the maximum serum level was raised by almost 20%. These modest changes were not considered clinically relevant. ... 

After taking verapamil 80 mg three times daily for 3 days, the clearance of a single 400-mg dose of quinidine sulphate in 6 healthy subjects was decreased by 32% and the half-life was increased by 35% from 6.87 to 9.29 hours. 

Quinidine sulphate 200 mg was given to 10 healthy subjects, followed 1 hour later by a single 400-mg dose of indinavir. Quinidine had no clinically significant effects on the pharmacokinetics of indinavir. However, indinavir is predicted to increase quinidine levels, and the US manufacturer recommends caution and monitoring of quinidine ieveis. Lopinavir/ritonavir is also predicted to increase quinidine levels, and the combination should be monitored. Similarly, atazanavir/ritonavir, darunavir/ritonavir, amprenavir and fosamprenavir ate predieted to increase quinidine levels, and the UK manufacturers contraindieate the combinations "" while the US manufacturers recommend monitoring quinidine concentrations. Conversely, for saquinavir/ritonavir, the UK manufacturer recommends caution and monitoring quinidine levels, and the US manufacturer eontraindicates the combination. Both the UK and US manufacturers contraindicate the use of quinidine with nelfinavir, ritonavir or tipranavir/ritonavir. ... 

Bodmeier R, McGinity JW. Polylactic acid microspheres containing quinidine base and quinidine sulphate prepared by the solvent evaporation technique. I. Methods and morphology. Journal of Microencapsulation. October-December 1987 4(4) 279-288. PubMed PMID 3504509. 

Ascorbic acid (+)-calcium pantothenate (-)-carvone anhydrous dextrose ephedrine hydrochloride (+)-litnonene L-lysine mannitol monosodium glutamate norephedrine hydrochloride quinidine sulphate quinine sulphate sorbitol L-threonine L-tryptophan tartaric acid all amino acids most sugars, e.g., glucose, xylose, ribose. 

Occupational quinidine contact dermatitis has also been reported (Fernstrom 1965). The patient was an employee of a pharmaceutical company and was required to grind drugs into a powder. A positive patch test to crystals of quinidine sulphate confirmed the already strong clinical evidence. 

Quinidine sulphate, (C2oH2402N2)2,H2S04,2H20, Mol. Wt. 783 0, is assayed for its quinidine content by the method used for quinine salts. 

Tablets of Quinidine Sulphate, B.P, Usually. contain 3 grains of quinidine sulphate.

No difficulty is experienced in the chemical assay. A quantity of powdered tablets, equivalent to about 0 3 g of quinidine sulphate, is dissolved in acid and preferably filtered before extracting the base in the usual way. 

A patient on long-term treatment with primidone (which is metabolized to pheno-barbitone) was given quinidine sulphate, but the plasma levels achieved were much lower than expected. When primidone was withdrawn and quinidine sulphate continued in the same dose, the plasma quinidine concentration rose 3-fold the plasma quinidine half-Ufe was found to have lengthened from 5 hr to 12 hr. In a second patient given phenytoin and quinidine simultaneously, unusually high doses of quinidine were required to achieve adequate plasma quinidine concentrations. Withdrawal of phenytoin led to rising plasma quinidine concentrations and development of clinical toxicity. Subsequent studies in 4 normal subjects showed that administration of either phenobarbitone... 

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