Comparative Bioavailability of a Microsize and Ultramicrosize Griseofulvin Formulation in Man

1982 ◽  
Vol 10 (4) ◽  
pp. 274-277 ◽  
Author(s):  
C Lin ◽  
J Lim ◽  
C DiGiore ◽  
R Gural ◽  
bS Symchowicz
Keyword(s):  
Plasma Concentration ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Healthy Male ◽  
Time Curve ◽  
Concentration Time ◽  
Comparative Bioavailability ◽  
Plasma Concentration Time Curve ◽  
Randomized Crossover Study ◽  
Curve Maximum

The bioavailability of 500 mg of a microsize formulation of griseofulvin has been compared to two new ultramicrosize griseofulvin formulations, two 165 mg tablets and a 330 mg tablet, in sixteen healthy, male, volunteers in a randomized crossover study design. Based on the griseofulvin plasma levels measured at specified times over a 48-hour period, the major bioavailability parameters (i.e., area under plasma concentration-time curve, maximum plasma concentration, and time to reach maximum plasma concentration) were determined and statistically evaluated. The results showed that one 330 mg ultramicrosize tablet is bioequivalent to two 165 mg ultramicrosize griseofulvin tablets and that either ultramicrosize griseofulvin dosage regimen is bioequivalent to 500 mg of the microsize griseofulvin formulation.

scholarly journals Multiple-Dose Safety, Tolerability, and Pharmacokinetics of Oral Nemonoxacin (TG-873870) in Healthy Volunteers

2010 ◽  
Vol 54 (1) ◽  
pp. 411-417 ◽  
Author(s):  
David T. Chung ◽  
Cheng-Yuan Tsai ◽  
Shu-Jen Chen ◽  
Li-Wen Chang ◽  
Chi-Hsin R. King ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Healthy Volunteers ◽  
Bacterial Infections ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Time Curve ◽  
Once Daily ◽  
Concentration Time ◽  
Atypical Pathogens ◽  
Plasma Concentration Time Curve

ABSTRACT Nemonoxacin (TG-873870) is a novel nonfluorinated quinolone with broad-spectrum activities against Gram-positive and Gram-negative aerobic, anaerobic, and atypical pathogens, as well as against methicillin-resistant Staphylococcus aureus, vancomycin-resistant S. aureus, and multiple-resistant bacterial pathogens. We conducted a randomized, double-blind, placebo-controlled, dose-escalating study to ascertain the safety, tolerability, and pharmacokinetics of nemonoxacin. We enrolled 46 healthy volunteers and used a once-daily oral-dosing range of 75 to 1,000 mg for 10 days. Additionally, the food effect was evaluated in subjects in the 500-mg cohort. Nemonoxacin was generally safe and well tolerated, with no significant changes in the clinical laboratory tests or electrocardiograms. Adverse effects, including headache, contact dermatitis, and rash, were mild and resolved spontaneously. Nemonoxacin was rapidly absorbed within 2 h postdosing, and generally, a steady state was reached after 3 days. The maximum plasma concentration and the area under the plasma concentration-time curve were dose proportional over the dosing range. The elimination half-life was approximately 7.5 h and 19.7 h on days 1 and 10, respectively. Approximately 37 to 58% of the drug was excreted in the urine. Food affected the pharmacokinetics, with decreases in the maximum plasma concentration and area under the plasma concentration-time curve of 46% and 27%, respectively. However, the free AUC/MIC90 of nemonoxacin was more than 100 under both the fasting and fed conditions, predicting the efficacy of nemonoxacin against most of the tested pathogens. In conclusion, the results support further clinical investigation of once-daily nemonoxacin administration for antibiotic-sensitive and antibiotic-resistant bacterial infections.

Pharmacokinetics of an immunomodulating dose of levamisole in weaned pigs

2013 ◽  
Vol 61 (3) ◽  
pp. 376-382
Author(s):  
Jelena Šuran ◽  
Dubravka Flajs ◽  
Maja Peraica ◽  
Andreja Prevendar Crnić ◽  
Marcela Šperanda ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Area Under The Curve ◽  
Maximum Plasma ◽  
Weaned Pigs ◽  
Time Curve ◽  
Treatment Groups ◽  
Parallel Design ◽  
Concentration Time ◽  
Plasma Concentration Time Curve ◽  
Crossbred Pigs

Levamisole has been shown to stimulate the immune response in immunocompromised humans and animals. However, its use as an adjuvant in immunocompromised weaned pigs prone to colibacillosis has only been experimentally tested but not yet officially approved. Therefore, the aim of these studies was to study the pharmacokinetics (PK) of an immunomodulating dose of levamisole in weaned pigs. For that purpose, 20 weaned crossbred pigs were divided into two treatment groups. In this parallel-design study, a single dose of levamisole (2.5 mg/kg body weight) was administered by the intramuscular (i.m.) or oral (p.o.) route. Statistically significant differences between the i.m. and p.o. routes in terminal beta rate constant (β), maximum plasma concentration (Cmax), area under the curve (AUC) for plasma concentration-time curve from time zero to infinity (AUC0-inf), area under the plasma concentration-time curve from time 0 to the last quantifiable time point (AUC0-t) were determined. Further research is needed to establish a relationship between the PK and the immunomodulating effect of levamisole in pigs.

The Pharmacokinetics of Loratadine in Normal Geriatric Volunteers

1988 ◽  
Vol 16 (1) ◽  
pp. 50-60 ◽  
Author(s):  
J. Hilbert ◽  
V. Moritzen ◽  
A. Parks ◽  
E. Radwanski ◽  
G. Perentesis ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
High Performance ◽  
The Elderly ◽  
Maximum Plasma Concentration ◽  
Pharmacokinetic Analysis ◽  
Maximum Plasma ◽  
Open Label ◽  
Post Dose ◽  
Time Curve ◽  
Concentration Time

The pharmacokinetics of loratadine, a non-sedating anti-histamine, were studied in 12 normal geriatric volunteers. In an open label fashion, each volunteer received one 40 mg loratadine capsule. Blood was collected prior to and at specified times (up to 120 h) after dosing. Plasma loratadine concentrations were determined by a specific radioimmunoassay and those of an active metabolite, descarboethoxyloratadine, by high performance liquid chromatography. Concentrations of loratadine in the disposition phase were fitted to a biexponential equation and those of descarboethoxyloratadine to either a monoexponential or biexponential equation for pharmacokinetic analysis. Loratadine was rapidly absorbed, reaching a maximum plasma concentration of 50.5 ng/ml at 1.5 h after dosing. The disposition half-lives of loratadine in the distribution and elimination phases were 1.5 and 18.2 h, respectively. The area under the plasma concentration–time curve, was 146.7 h·ng/ml. Descarboethoxyloratadine had a maximum plasma concentration of 28.0 ng/ml at 2.9 h post-dose and an area under the concentration–time curve of 394.9 h·ng/ml. Its disposition half-lives in the distribution and elimination phases were 2.8 and 17.4 h, respectively. Comparison of these data with those from a previous study of loratadine in young adults showed no clear differences in the disposition half-lives between the two groups. The clearance of loratadine tends to be lower in the elderly, but inter-individual variation within each age group appears greater than any age effect.

scholarly journals Pharmacokinetics of toltrazuril and its metabolites toltrazuril sulphoxide and toltrazuril sulphone in pregnant and non-pregnant goats

2021 ◽  
Vol 90 (4) ◽  
pp. 383-390
Author(s):  
Sara T. Elazab ◽  
Nahla S. Elshater ◽  
Ahmed E. Elweza
Keyword(s):  
Plasma Concentration ◽  
Volume Of Distribution ◽  
Maximum Plasma ◽  
Time Curve ◽  
Concentration Time ◽  
Elimination Half ◽  
Plasma Concentration Time Curve ◽  
Group 2 ◽  
Post Therapy ◽  
Group 1

The pharmacokinetic characteristics of toltrazuril (TZR) and its metabolites toltrazuril sulphoxide (TZR.SO) and toltrazuril sulphone (TZR.SO2) were assessed in non-pregnant and pregnant goats. Ten healthy Baladi female goats were allocated into two groups (n = 5 per group): non-pregnant goats (group 1) and pregnant goats at 2–3 months of gestation (group 2). Toltrazuril was administered once orally to all goats at 20 mg/kg. Plasma samples were collected at 0 (before TZR administration), 0.5, 1, 2, 4, 6, 8, 12, 16, 24, 48, 72 h and 5, 7, 9, 12, 16, 20, 24, 27, 30, and 35 days post therapy to measure the concentrations of TZR and its metabolites. In pregnant goats, the maximum plasma concentration (Cmax), time to reach Cmax (Tmax), and the area under the plasma concentration-time curve from time zero to the last sample (AUC0-last) of TZR were significantly higher (P < 0.05) compared to the non-pregnant ones, whereas the volume of distribution (Vz_F_obs) and clearance (Cl_F_obs) were significantly lower (P < 0.05) in pregnant goats. No significant differences were observed in the elimination half-life (T1/2λz), and mean residence time (MRT) between the two groups. In non-pregnant goats, TZR.SO and TZR.SO2 could be detected in plasma until 12 and 30 days, respectively; whereas in pregnant goats, they were quantified up to 16 and 35 days, respectively. Conclusively, TZR was well absorbed and rapidly metabolized to TZR.SO and TZR.SO2, after oral dosing in goats. Pregnancy caused significant alterations in some of the pharmacokinetic indicators of TZR and its metabolites in goats.

scholarly journals Comparative bioavailability study of phenytoin in healthy Nepalese volunteers

2019 ◽  
Vol 9 (1-s) ◽  
pp. 144-147
Author(s):  
DIllisher Rai ◽  
Gajendra Prasad Rauniar
Keyword(s):  
Plasma Concentration ◽  
Peak Plasma ◽  
Peak Plasma Concentration ◽  
Elimination Rate ◽  
P Value ◽  
Maximum Plasma ◽  
Time Curve ◽  
Oral Tablet ◽  
Concentration Time ◽  
Plasma Concentration Time Curve

Our study aimed to assess and compare the bioavailability of Eptoin 100 mg and Epileptin 100mg tablets in Nepalese healthy volunteers. A randomized, two-treatment cross-over study with two weeks’ wash-out period was conducted in 12 healthy non-smoker and non-alcoholic Nepalese male volunteers over a period of 6 months in the department of Clinical Pharmacology and Therapeutic at B. P. Koirala Institute of Health Sciences, Dharan, Nepal after approval from the Institutional Review Committee. The participants were randomized using sealed envelope system and received a single 100 mg oral tablet of either of the formulations with a two week washout period. Blood samples were collected predose and at regular intervals postdose upto 72 hours. Plasma phenytoin levels were estimated by reverse phase high performance liquid chromatography. The analytical method was validated prior to the start of study. Cmax (Peak Plasma Concentration), Tmax (Time to achieve maximum Plasma Concentration), AUC0-72 (Area under plasma concentration time curve 0 to 72 hours), AUC0-∞ (Area under plasma concentration time curve 0 to ∞) and T½ (Elimination half-life) and Kel (Elimination rate constant) were calculated and 80-120% margin (90% confidence interval) was used to assess bioequivalence. ANOVA test was used to analyze the data at P-value of 0.05. All volunteers completed the study. The log-transformed values of Cmax, Tmax, AUC0-t, and AUC0-∞ of the both formulations were within the specified limits and were bioequivalent according to the regulatory definition of bioequivalence based on the rate and extent of absorption. Both products can be considered equally effective in medical practice. Keywords: Bioavailability, Bioequivalence, healthy volunteer, Nepal, phenytoin sodium.

Pharmacokinetic interaction between linagliptin and tadalafil in healthy Egyptian males using a novel LC–MS method

Bioanalysis ◽  
2019 ◽  
Vol 11 (14) ◽  
pp. 1321-1336 ◽  
Author(s):  
Sara S Mourad ◽  
Eman I El-Kimary ◽  
Magda A Barary ◽  
Dalia A Hamdy
Keyword(s):  
Plasma Concentration ◽  
Pharmacokinetic Interaction ◽  
Volume Of Distribution ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Qtc Interval ◽  
Qtc Prolongation ◽  
Open Label ◽  
Time Curve ◽  
Concentration Time

Aim: Assessment of pharmacokinetic interaction between linagliptin (LNG) and tadalafil (TDL) in healthy males. Methods: First, a novel LC–MS method was developed; second, a Phase IV, open-label, cross-over study was performed. Volunteers took single 20-mg TDL dose on day 1 followed by wash out period of 2 weeks then multiple oral dosing of 5-mg/day LNG for 13 days. On day 13, volunteers were co-administered 20-mg TDL. Results: LNG and TDL single doses did not affect QTc interval. Smoking did not alter pharmacokinetics/pharmacodynamics of LNG and TDL. Co-administration of LNG with TDL resulted in TDL longer time to reach maximum plasma concentration (Tmax), decreased oral clearance (Cl/F) and oral volume of distribution (Vd/F), increased its maximum plasma concentration (Cmax), area under concentration-time curve (AUC), muscle pain and QTc prolongation. Conclusion: LNG and TDL co-administration warrants monitoring and/or TDL dose adjustment.

Comparative Bioavailability of d-pseudoephedrine from a Conventional d-pseudoephedrine Sulfate Tablet and from a Repeat Action Tablet

1982 ◽  
Vol 10 (2) ◽  
pp. 126-128
Author(s):  
C Lin ◽  
J Lim ◽  
S Symchowicz
Keyword(s):  
Plasma Concentration ◽  
Tablet Formulation ◽  
Maximum Plasma ◽  
Time Curve ◽  
Tablet Form ◽  
Conventional Tablet ◽  
Concentration Time ◽  
Equivalent Quantity ◽  
Significant Difference ◽  
Comparative Bioavailability

The bioavailability of a single dose of d-pseudoephedrine sulfate administered to male volunteers in repeat action tablet* form (60 mg d-pseudoephedrine sulfate in the coat and 60 mg d-pseudoephedrine sulfate in the core) was compared with the bioavailability of an equivalent quantity of the drug given as two 60 mg conventional tablets, one given at 0 hour and the second 6 hours later. There was no significant difference (p > 0·10) between the conventional tablets and the repeat action tablet formulation in area under the plasma concentration-time curve and the maximum plasma concentration of d-pseudoephedrine. Based on the data, we conclude that the repeat action tablet formulation and the conventional tablet are bioequivalent.

Comparative Bioavailability and Safety of Two Intramuscular Ceftriaxone Formulations

1996 ◽  
Vol 30 (11) ◽  
pp. 1223-1226 ◽  
Author(s):  
Encarnación C Suárez ◽  
Jana R Grippi
Keyword(s):  
Plasma Concentration ◽  
Pharmacokinetic Parameters ◽  
Maximum Plasma ◽  
Double Blind ◽  
Time Curve ◽  
Mean Values ◽  
Concentration Time ◽  
Clinical Research Center ◽  
Comparative Bioavailability ◽  
Concentrated Solution

OBJECTIVE: To determine if two ceftriaxone solutions of different concentrations are bioequivalent when administered intramuscularly. DESIGN: Double-blind, single-dose, two-period, randomized crossover study. SETTING: A clinical research center. SUBJECTS: Seventeen healthy volunteers. INTERVENTION: Ceftriaxone 500 mg administered in either 2 or 1.4 mL of lidocaine 1% solution, with final ceftriaxone concentrations of 250 and 350 mg/mL, respectively. MAIN OUTCOME MEASURES: Blood samples were assayed for ceftriaxone concentrations with HPLC and pharmacokinetic parameters were calculated from the resulting plasma—concentration time profiles: maximum plasma concentration (Cmax) of ceftriaxone and areas under the concentration-time curve (AUC) from 0 to 36 h and 0 to infinity were the primary parameters considered in the determination of bioequivalence. RESULTS: The two solutions were generally well tolerated and had similar safety profiles. Administration of both solutions resulted in similar mean values for all pharmacokinetic parameters. Statistical analysis showed no significant differences between the two solutions in any pharmacokinetic parameter, indicating that the two solutions are statistically bioequivalent (p ≤ 0.05). The 90% CI for the ratio of the means for AUC0-36 (0.86 to 1.11), AUC0-∞. (0.89 to 1.14), and Cmax (0.84 to 1.12) are within the Food and Drug Administration range of bioequivalence (0.80 to 1.25). CONCLUSIONS: These results demonstrate that the more concentrated solution of ceftriaxone (350 mg/mL) is bioequivalent to the currently marketed solution of 250 mg/mL.

Bioavailability of d-pseudoephedrine and Azatadine from a Repeat Action Tablet Formulation

1982 ◽  
Vol 10 (2) ◽  
pp. 122-125
Author(s):  
C Lin ◽  
J Lim ◽  
S Symchowicz
Keyword(s):  
Plasma Concentration ◽  
Tablet Formulation ◽  
Maximum Plasma Concentration ◽  
Maximum Plasma ◽  
Gas Liquid Chromatography ◽  
Time Curve ◽  
Conventional Tablet ◽  
Cumulative Urinary Excretion ◽  
Significant Difference ◽  
Curve Maximum

The objective of this study was to compare in man the bioavailability of d-pseudoephedrine and azatadine from a repeat action tablet* formulation and from conventional tablets. The repeat action tablet, containing 1 mg of azatadine maleate in the coat, and 60 mg of d-pseudoephedrine sulfate in both the coat and the core, was given at 0 hour. A conventional tablet of 60 mg of d-pseudoephedrine sulfate was given at 0 and 4 hours and a conventional tablet of 1 mg of azatadine maleate was given at 0 hour. The plasma levels of d-pseudoephedrine were measured by gas-liquid chromatography and the amount of azatadine in the urine was determined by a mass fragmentographic procedure. The results showed that there were no statistically significant differences in the measured bioavailability parameters (area under plasma concentration-time curve, maximum plasma concentration and time to reach maximum plasma concentration) for pseudoephedrine from repeat action tablets and conventional d-pseudoephedrine sulfate tablets; neither was there any statistically significant difference in the cumulative urinary excretion of azatadine from the repeat action tablets and conventional azatadine maleate tablets (p > 0·10). These data clearly demonstrate the bioequivalence of the repeat action tablets and the conventional tablets of d-pseudoephedrine and azatadine.

Exposure to Retinoic Acids in Non-Pregnant Women Following High Vitamin A Intake with a Liver Meal

2005 ◽  
Vol 75 (3) ◽  
pp. 187-194 ◽  
Author(s):  
Hartmann ◽  
Brørs ◽  
Bock ◽  
Blomhoff ◽  
Bausch ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Vitamin A ◽  
Safety Concern ◽  
Peak Plasma ◽  
Plasma Concentrations ◽  
Pregnant Female ◽  
Time Curve ◽  
High Vitamin ◽  
Concentration Time ◽  
Plasma Concentration Time Curve

Animal liver is a rich source of vitamin A. Due to retinoic acid (RA) metabolites, vitamin A has a teratogenic potential and women are generally advised to avoid or to limit the consumption of liver during pregnancy. In a recent study in non-pregnant female volunteers following single and repeated doses of up to 30,000 IU/day of vitamin A as a supplement, the plasma concentration time curve of all-trans RA acid showed a diurnal-like profile. But, the overall exposure (AUC24h) remained essentially unaltered whereas AUC24h increased linearly with dose for 13-cis and 13-cis-4-oxo RA. The current study in non-pregnant female volunteers showed that a single high vitamin A intake with a liver meal (up to 120,000 IU) exhibited a similar diurnal-like plasma concentration time curve for all-trans RA and its overall exposure remained also unaltered, despite a temporary two-fold increase in peak plasma concentration. Concentrations of 13-cis and 13-cis-4-oxo RA increased several-fold after a liver meal, and exposure (AUC24h) increased three- to five-fold. Pooling our results with data in the literature revealed a linear relation between the mean AUC24h of 13-cis and 13-cis-4-oxo RA and vitamin A intake with liver. Metabolism to all-trans RA of vitamin A with liver seems not to be of safety concern. However, the observed increase of plasma concentrations and the dose-dependent increase in exposure to 13-cis and 13-cis-4-oxo RA support the current safety recommendations on vitamin A intake and suggest that women should be cautious regarding their consumption of liver-containing meals during pregnancy.

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