Comparative bioavailability study of cefuroxime axetil (equivalent to 500 mg cefuroxime/tablet) tablets (Zednad® versus Zinnat®) in healthy male volunteers.

This study was performed to investigate the bioequivalence of cefuroxime axetil tablets between a generic test product (A) Zednad® Tablet (500 mg cefuroxime/ tablet, Diamond Pharma, Syria), and the Reference Product (B) Zinnat® Tablet (500 mg cefuroxime/tablet, GlaxoSmithKline, Saudi Arabia). The bioavailability study was carried out for 24 healthy male volunteers. The subjects received 1 Zednad® Tablet (500 mg/ tablet) and 1 Zinnat® Tablet (500 mg/tablet) in a randomized, two-way crossover design fashion on 2 treatment days, after an overnight fast of at least 10 h, with a washout period of 7 days.

Bioequivalence evaluation of 320 mg gemifloxacin tablets in healthy volunteers.

This study was done to compare the bioavailability of a new tablet formulation of gemifloxacin (gemifloxacin 320 mg/tablet) with that of the reference product (factive 320 mg/tablet). The bioequivalence of a single dose (320 mg) was assessed for gemifloxacin included in the test and reference products by comparing the pharmacokinetic parameters derived from the plasma concentration-time profiles following administration to 24 healthy male volunteers in a balanced, 2-period, 2-sequence, 2-way crossover design. Plasma concentrations of gemifloxacin were analyzed by a validated and sensitive HPLC assay developed in-house.

Comparative bioavailability study of cefixime (equivalent to 100 mg/5 ml) suspension (Winex vs Suprax) in healthy male volunteers.

This investigation was carried out to evaluate the bioavailability of a new suspension formulation of cefixime (100 mg/5 ml), Winex, relative to the reference product, Suprax (100 mg/5 ml) suspension. The bio-availability study was carried out in 24 healthy male volunteers who received a single oral dose (200 mg) of the test (A) and the reference (B) products on 2 treatment days after an overnight fast of at least 10 hours. The treatment periods were separated by a one-week washout period.

Comparative bioavailability study of doxycycline hyclate (equivalent to 100 mg doxycycline) capsules (doxycin vs vibramycin) for bioequivalence evaluation in healthy adult volunteers.

This investigation was carried out to evaluate the bioavailability of a new capsule formulation of doxycycline (100 mg), doxycin, relative to the reference product, vibramycin (100 mg) capsules. The bioavailability was carried out in 24 healthy male volunteers who received a single dose (100 mg) of the test (A) and the reference (B) products after an overnight fast of at least 10 hours on 2 treatment days. The treatment periods were separated by a 2-week washout period.

Effect of lamotrigine on the pharmacokinetics of carbamazepine and its active metabolite in dogs.

The effect of lamotrigine (LTG) on the pharmacokinetics of carbamazepine (CBZ) and its active metabolite; carbamazepine-epoxine (CBZ-E), was investigated in dogs. Five male dogs received CBZ (2 x 200 mg tab, p.o.

Bioequivalence evaluation of two brands of cefuroxime 500 mg tablets (Cefuzime and Zinnat) in healthy human volunteers.

A bioequivalence study of two oral formulations of 500 mg cefuroxime axetil was carried out in 24 healthy volunteers following a single dose, standard two-treatment cross-over design at the College of Pharmacy, King Saud University, Riyadh, Saudi Arabia, working jointly with King Khalid University Hospital. The two formulations used were Cefuzime (Julphar, United Arab Emirates) as the test and Zinnat (Glaxo Wellcome, England) as the reference product. Both test and reference tablets were administered to each subject after an overnight fasting on two treatment days separated by a 1-week washout period.

Bioequivalence evaluation of norfloxacin 400 mg tablets (Uroxin and Noroxin) in healthy human volunteers.

A bioequivalence study of two oral formulations of 400 mg norfloxacin was carried out in 18 healthy volunteers according to a single dose, two-sequence, cross-over randomized design at College of Pharmacy, King Saud University, Riyadh, Saudi Arabia, jointly with King Khalid University Hospital. The two formulations were: Uroxin (Julphar, United Arab Emirates) as test and Noroxin (Merck Sharpe & Dohme, BV, Netherlands). Both test and reference formulations were administered to each subject after an overnight fasting on 2 treatment days separated by 1 week wash-out period.

Bioequivalence evaluation of lomefloxacin 400 mg tablets (Lomax versus Maxaquin in healthy human volunteers.

This study represents the results of a randomized, single dose, two-treatment, two-period crossover study in 18 healthy male volunteers to assess the bioequivalence of two tablets of 400 mg lomefloxacin. The two formulations were: Lomax(R) (Julphar, United Arab Emirates) as the test formulation and Maxaquin(R) (Searle, S.A.

Liquid chromatographic assay of nifedipine in human plasma and its application to pharmacokinetic studies.

A highly sensitive, selective and reproducible reversed-phase high-performance liquid chromatographic method has been developed for the determination of nifedipine in human plasma with minimum sample preparation. The method is sensitive to 3 ng/ml in plasma, with acceptable within- and between-day reproducibilities and linearity (r2 > 0.99) over a concentration range from 10-200 ng/ml.

Phenytoin dosage adjustment in Saudi epileptics: utilization of steady-state pharmacokinetic parameters.

We determined the Michaelis-Menten parameters (Vmax and Km) in 271 Saudi epileptic patients having generalized tonic-clonic seizures and who were treated with phenytoin (PHT) using high pressure liquid chromatography (HPLC). The patients comprised 150 (55.4%) males and 121 (44.

High-performance liquid chromatographic determination of furosemide in plasma and urine and its use in bioavailability studies.

A sensitive, selective and efficient reversed-phase high-performance liquid chromatographic (HPLC) method is reported for the determination of furosemide in human plasma and urine. The method has a sensitivity limit of 5 ng/ml in plasma, with acceptable within- and between-day reproducibilities and good linearity (r2>0.99) over a concentration range from 0.

Comparative bioavailability of two tablet formulations of ranitidine hydrochloride in healthy volunteers.

This investigation was carried out to evaluate the bioavailability of a new tablet formulation of ranitidine HCl (300 mg), Ranid, relative to the reference product, Zantac, (300 mg) tablets. The bioavailability was carried out on 24 healthy male volunteers who received a single dose (300 mg) of the test (T) and the reference (R) products in the fasting state, in a randomized balanced 2-way crossover design. After dosing, serial blood samples were collected for a period of 16 hours.

Comparative bioavailability of two tablet formulations of acyclovir in healthy volunteers.

This investigation was carried out to evaluate the bioavailability of a new tablet formulation of acyclovir (400 mg), Clovir, relative to reference product, Zovirax (400 mg) tablets. The 2 brands were found to be similar in weight variation, disintegration time, dissolution, and assay as stipulated by the USPXXIII, as well as by the manufacturer. The bioavailability was carried out on 24 healthy male volunteers who received a single dose (400 mg) of the test (T) and the reference (R) products in the fasting state, in a randomized balanced 2-way crossover design.

Determination of pefloxacin and its main active metabolite in human serum by high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method is described for the simultaneous determination of a fluoroquinolone, pefloxacin, and its main active metabolite norfloxacin (N-desmethyl metabolite) in serum. Sample preparation involves protein precipitation with acetonitrile. The drugs and the internal standard (acebutolol) were eluted from a 4-microns Novapak C-18 cartridge at ambient temperature with an isocratic mobile phase consisting of 14% acetonitrile in buffer solution, at a flow rate of 2.

Comparative bioavailability of two tablet formulations of ibuprofen.

This investigation was carried out to evaluate the bioavailability of a new tablet formulation of ibuprofen (600 mg), Profinal, relative to reference product, Brufen (600 mg) tablets. The 2 brands were found to be similar in assay, weight variation and dissolution as stipulated by the USP XXII, as well as the disintegration time, as specified by the BP 1988. The bioavailability was carried out on 18 healthy male volunteers who received a single dose (600 mg) of the test (T) and the reference (R) products in the fasting state, in a randomized balanced 2-way crossover design.

Effect of famotidine on ciprofloxacin pharmacokinetics after single intravenous and oral doses in rats.

The effect of intravenous (3.5 mg/kg) and oral (5 mg/kg) famotidine on ciprofloxacin pharmacokinetics after single (i.v.

Microcomputer program for the assessment of one-way, two-way and factorial analysis of variance in pharmaceutical data.

A personal computer program in BASIC for the two-factor factorial analysis of variance has been developed. The factorial design is based on and combined with previous one-way and two-way ANOVA programs. The performance of the program is tested on data obtained from 3 months' consumption of three proprietary antibiotic products in four Saudi hospitals.

Effect of pirenzepine on the N-demethylation of D(-)ephedrine and ethylmorphine by rabbit liver microsomes.

The possible interaction of pirenzepine with the mixed-function oxidases obtained from phenobarbital-pretreated rabbit microsomes was examined in vitro. Under experimental conditions that did not lead to its own N-demethylation, the drug inhibited the microsomal oxidase systems responsible for the N-demethylation of D(-)ephedrine and ethylmorphine. Kinetic studies showed that pirenzepine inhibited the metabolism of both drugs in a competitive manner.

A simple high-performance liquid chromatographic assay for ciprofloxacin in human serum.

A simple and selective high-performance liquid chromatographic (HPLC) method for the determination of ciprofloxacin in serum has been developed and evaluated. Serum protein was precipitated with acetonitrile. The drug and the internal standard (quinine) were evaluated from a 10 microns U-Bondapack C-18 cartridge at ambient temperature with a mobile phase consisting of acetonitrile: 0.

Comparative study of Saudi-marketed products and US drug labeling.

Drug package inserts from ten nonsteroidal antiinflammatory drugs marketed in Saudi Arabia were compared with their corresponding US labels to determine possible differences in their information content. These variations were assessed with special regard to the number of words used and the type of the information provided. The study showed that inserts of Saudi-marketed products generally conveyed limited and incomplete information.

Phenytoin-bupropion interaction: effect on plasma phenytoin concentration in the rat.

The effect of coadministration of bupropion (50 mg kg-1, p.o.) on the disposition profile of phenytoin has been studied in the rat.

Evaluation of hepatic dysfunction in endotoxin pretreated rats using tolbutamide as a marker.

The pharmacokinetics of tolbutamide (TB) have been studied in endotoxin pretreated rats with the aim of evaluating TB as a marker for endotoxin effects. Endotoxin dose of 10 mg/kg resulted in a 50% rate of mortality. TB was i.

First-derivative UV spectrophotometric assay of domperidone.

Domperidone in pure form and in a number of pharmaceutical formulations (Motilium) has been determined in 0.5-N sulphuric acid by employing first-derivative at 294 nm and zero-order at 284 nm spectrophotometric modes. The results obtained by utilizing the first derivative procedure were 99.

Disposition kinetics of cimetidine and ranitidine in endotoxin pretreated rats.

Cimetidine and ranitidine are used in patients with life-threatening gram-negative infections, endotoxemia and acute stress erosions. Disposition kinetics of cimetidine and ranitidine in endotoxin pretreated rats was investigated. The H2-antagonists were administered intravenously 24 h after endotoxin (10 mg/kg) pretreatment.

Effect of bupropion on cimetidine and ranitidine absorption in rats.

Cimetidine and ranitidine absorption were studied in rats, alone or in combination with concurrent but separate bupropion oral administration. Blood samples were collected before and 0.25, 0.