BIODYNAMICS OF 1.2α-METHYLENE-6-CHLORO-PREGNA-4,6-DIEN-17α-OL-3,20-DIONE (CYPROTERONE) IN MAN FOLLOWING ORAL AND INTRAVENOUS ADMINISTRATION

1970 ◽  
Vol 64 (2) ◽  
pp. 228-252 ◽  
Author(s):  
E. Gerhards ◽  
H. Röpke ◽  
P. E. Schulze ◽  
H. Hitze
Keyword(s):  
Oral Dose ◽  
Oral Administration ◽  
Ethyl Acetate ◽  
Intravenous Administration ◽  
Perchloric Acid ◽  
Half Life ◽  
Analogue Computer ◽  
Elimination Half ◽  
Deep Compartment ◽  
Intravenous And Oral Administration

ABSTRACT The metabolism and pharmacokinetics (biodynamics) of 1,2α-methylene-[14C]-6-chloro-pregna-4,6-dien-17α-ol-3,20-dione (Cyproterone; Cy) have been investigated in man following intravenous and oral administration. The principal metabolite in the plasma following the intravenous and oral administration is 1,2α-methylene-6-chloro-pregna-4,6-diene-17α,20α-diol-3-one (20α-OH-Cy). After a single oral dose of 100 mg Cy, the concentration of unchanged free Cy during the first 24 hours is about 1 μg/100 ml plasma. Of 100 mg Cy administered p. o., only about 40% was absorbed, 60% being eliminated in the faeces. In the urine, 20α-OH-Cy and 1,2α-methylene-6-chloro-androst-4,6-diene-3,17-dione(17-keto-Cy) were isolated and identified as the principal metabolites. About 60% of the radioactivity in the urine, following oral and intravenous administration of [14C]-Cy, is present in the form of watersoluble compounds (conjugates) which cannot be decomposed either with enzymes (β-glucuronidase, sulphatase) or by means of cold or hot acid hydrolysis. Decomposition by solvolysis with perchloric acid in ethyl acetate, however, is quantitative. On the basis of simulation performed with an analogue computer, the elimination half-life of the deep compartments following intravenous or oral administration of Cy would be between 3 and 5 days, on the basis of 14C-activity. 'Oral administration' of 100 mg Cy daily, as simulated on the analogue computer, is cumulative; an equilibrium in the deep compartment being reached only after about 28 days and that in the blood after about 14 days.

scholarly journals Pharmacokinetics and skin concentrations of lincomycin after intravenous and oral administration to cats

2013 ◽  
Vol 84 (1) ◽  
Author(s):  
Gabriela A. Albarellos ◽  
Laura Montoya ◽  
Graciela A.A. Denamiel ◽  
Sabrina M. Passini ◽  
María F. Landoni
Keyword(s):  
Plasma Concentration ◽  
Oral Administration ◽  
Intravenous Administration ◽  
Half Life ◽  
Pharmacokinetic Profile ◽  
Maximum Plasma ◽  
Elimination Half Life ◽  
Concentration Time ◽  
Elimination Half ◽  
Intravenous And Oral Administration

The aim of the present study was to describe the plasma pharmacokinetic profile and skin concentrations of lincomycin after intravenous administration of a 15% solution and oral administration of 300 mg tablets at a dosing rate of 15 mg/kg to cats. Susceptibility of staphylococci (n = 31) and streptococci (n = 23) strains isolated from clinical cases was also determined. Lincomycin plasma and skin concentrations were determined by microbiological assay using Kocuria rhizophila ATCC 9341 as test microorganism. Susceptibility was established by the antimicrobial disc diffusion test. Individual lincomycin plasma concentration–time curves were analysed by a non-compartmental approach. After intravenous administration, volume of distribution, body clearance and elimination half-life were 0.97 L/kg ± 0.15 L/kg, 0.17 L/kg ± 0.06 L/h.kg and 4.20 h ± 1.12 h, respectively. After oral administration, peak plasma concentration, time of maximum plasma concentration and bioavailability were 22.52 µg/mL ± 10.97 µg/mL, 0.80 h ± 0.11 h and 81.78% ± 24.05%, respectively. Two hours after lincomycin administration, skin concentrations were 17.26 µg/mL ± 1.32 µg/mL (intravenous) and 16.58 µg/mL ± 0.90 µg/mL (oral). The corresponding skin: plasma ratios were 2.08 ± 0.47 (intravenous) and 1.84 ± 0.97 (oral). The majority of staphylococci and streptococci tested in this study were susceptible to lincosamides (87.09% and 69.56%, respectively). In conclusion, lincomycin administered orally at the assayed dose showed a good pharmacokinetic profile, with a long elimination half-life and effective skin concentration. Therefore, it could be a good first option for treating skin infections in cats.

Pharmacokinetic Evaluation of 3′-Azido-2′, 3′-Dideoxyuridine-5′-O-Valinate-Hydrochloride as a Prodrug of the Anti-HIV Nucleoside 3′-Azido-2′, 3′-Dideoxyuridine

2003 ◽  
Vol 14 (5) ◽  
pp. 263-270
Author(s):  
Linghui Kong ◽  
John S Cooperwood ◽  
Shu-Hui Christine Huang ◽  
Chung K Chu ◽  
F Douglas Boudinot
Keyword(s):  
Oral Administration ◽  
Intravenous Administration ◽  
Oral Bioavailability ◽  
Half Life ◽  
Dose Range ◽  
Parent Compound ◽  
Terminal Phase ◽  
Pharmacokinetic Parameters ◽  
Intravenous And Oral Administration ◽  
Anti Hiv

3′-Azido-2′, 3′-dideoxyuridine (AZDU, AzddU, CS-87) has been shown to have potent anti-HIV activity in vitro. However, the compound exhibits a relatively short half-life and incomplete oral bioavailability in humans. In an effort to improve the pharmacokinetic properties of AZDU, prodrug 3′-azido-2′,3′-dideoxyuridine-5′- O-valinate hydrochloride (AZDU-VAL) was synthesized by the esterification of 5′-OH function in AZDU. The objective of this study was to investigate the biotransformation and pharmacokinetics of AZDU-VAL along with its antiviral parent compound AZDU following intravenous and oral administration to rats. Adult male Sprague-Dawley rats were administered AZDU or AZDU-VAL by intravenous injection or oral gavage. Concentrations of AZDU-VAL and AZDU were determined by HPLC. Pharmacokinetic parameters were generated by area-moment analysis. The bioavailability of AZDU after oral administration was approximately 53%. The terminal phase half-life of the nucleoside analogue ranged between 0.6 h after intravenous administration and 1 h following oral administration. In vivo the prodrug was rapidly and efficiently biotransformed to yield AZDU following intravenous and oral administration. The apparent availability of AZDU was virtually complete following oral administration of prodrug AZDU-VAL averaging 101%. The bioavailability of AZDU following intravenous administration of AZDU-VAL averaged 106%. In summary, the disposition of AZDU was dose dependent over the dose range of 25–100 mg/kg. Renal clearance and steady state volume of distribution were lower at the higher dose level. Prodrug AZDU-VAL demonstrated improved oral bioavailability as evidenced by complete absorption and efficient bioconversion to AZDU. The results suggest that AZDU-VAL may be a promising prodrug for the delivery of AZDU.

scholarly journals Comparative Pharmacokinetics of Levofloxacin in Healthy and Renal Damaged Muscovy Ducks following Intravenous and Oral Administration

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Mohamed Aboubakr ◽  
Ahmed Soliman
Keyword(s):  
Serum Concentration ◽  
Oral Administration ◽  
Residence Time ◽  
Mean Residence Time ◽  
Half Life ◽  
Pharmacokinetic Profile ◽  
Total Clearance ◽  
Elimination Half ◽  
Muscovy Ducks ◽  
Intravenous And Oral Administration

The pharmacokinetics aspects of levofloxacin were studied in healthy and experimentally renal damaged Muscovy ducks after single intravenous (IV) and oral (PO) dose of 10 mg kg−1 bwt. Following IV administration, elimination half-life (t1/2(β)) and mean residence time (MRT) were longer in renal damaged ducks than in healthy ones. Total clearance(Cltot)in renal damaged ducks (0.20 L kg−1 h−1) was significantly lower as compared to that in healthy ones (0.41 L kg−1 h−1). Following PO administration, the peak serum concentration(Cmax)was higher in renal damaged than in healthy ducks and was achieved at maximum time(tmax)of 2.47 and 2.05 h, respectively. The drug was eliminated (t1/2(el)) at a significant slower rate (3.94 h) in renal damaged than in healthy ducks (2.89 h). The pharmacokinetic profile of levofloxacin is altered in renal damaged ducks due to the increased serum levofloxacin concentrations compared with that in clinically healthy ducks. Oral administration of levofloxacin at 10 mg kg−1 bwt may be highly efficacious against susceptible bacteria in ducks. Also, the dose of levofloxacin should be reduced in renal damaged ducks. Pharmacokinetic/pharmacodynamic integration revealed significantly higher values forCmax/MIC and AUC/MIC ratios in renal damaged ducks than in healthy ones, indicating the excellent pharmacokinetic characteristics of levofloxacin in renal damaged ducks.

Pharmacokinetic Comparison of Intravenous and Oral Chloramphenicol in Patients with Haemophilus in fluenzae Meningitis

PEDIATRICS ◽  
1981 ◽  
Vol 67 (5) ◽  
pp. 656-660
Author(s):  
Ram Yogev ◽  
William M. Kolling ◽  
Tommy Williams
Keyword(s):  
Serum Level ◽  
Oral Administration ◽  
Intravenous Administration ◽  
Half Life ◽  
Peak Serum ◽  
Peak Serum Level ◽  
Wide Range ◽  
Csf Levels ◽  
The Mean ◽  
Intravenous And Oral Administration

The pharmacokinetics of chloramphenicol following intravenous and oral administration were studied in 14 infants with Haemophilus influenzae meningitis. Following five days of treatment with intravenous chloramphenicol (100 mg/kg/day every six hours), oral chloramphenicol was substituted at the same dose. Multiple serum levels of chloramphenicol were determined after an intravenous dose on day 4 and after an oral dose on day 10. CSF levels were measured six hours after intravenous or oral chloramphenicol dose on those days (CSF trough). Following intravenous administration, the mean peak serum level of 15.0 µ/g ml was reached at 45 minutes. In comparison, after oral chloramphenicol in the same dosage, the mean peak serum level of 18.5 µg ml was achieved at two to three hours. The mean serum half-life of the drug (6.5 hours) was significantly longer after oral administration than after intravenous chloramphenicol (4.0 hours) (P .001). The increased serum half-life following orally administered chloramphenicol was occasionally associated with drug accumulation. In addition, mean trough CSF levels were somewhat higher when the patient received oral medication (6.6 µg/ml) compared to intravenous administration (4.2 µ/ml) (P .001). For any treatment regimen for H influenzae meningitis that includes a period of oral chloramphenicol therapy the patient should be hospitalized to ensure compliance. Because of the wide range of individual variation in serum half-life that may result in accumulation, periodic monitoring of serum chloramphenicol levels is also recommended.

scholarly journals Pharmacokinetics of Orally Administered Prednisolone in Alpacas

2021 ◽  
Vol 8 ◽  
Author(s):  
Ricardo Videla ◽  
Carla Sommardahl ◽  
Joe Smith ◽  
Deanna M. W. Schaefer ◽  
Sherry Cox
Keyword(s):  
Oral Administration ◽  
Half Life ◽  
Maximum Concentration ◽  
Healthy Adult ◽  
Area Under The Curve ◽  
Pharmacokinetic Parameters ◽  
Elimination Half Life ◽  
Cell Counts ◽  
Elimination Half ◽  
Intravenous And Oral Administration

This study aimed to determine the pharmacokinetics of prednisolone following intravenous and oral administration in healthy adult alpacas. Healthy adult alpacas were given prednisolone (IV, n = 4), as well as orally (PO, n = 6). Prednisolone was administered IV once (1 mg/kg). Oral administration was once daily for 5 days (2 mg/kg). Each treatment was separated by a minimum 4 month washout period. Samples were collected at 0 (pre-administration), 0.083, 0.167, 0.25, 0.5, 0.75, 1, 2, 4, 8, 12, and 24 h after IV administration, and at 0 (pre-administration), 0.25, 0.5, 0.75, 1, 2, 4, 8, 12, 24 after the first and 5th PO administration. Samples were also taken for serial complete blood count and biochemistry analysis. Prednisolone concentration was determined by high pressure liquid chromatography. Non-compartmental pharmacokinetic parameters were then determined. After IV administration clearance was 347 mL/kg/hr, elimination half-life was 2.98 h, and area under the curve was 2,940 h*ng/mL. After initial and fifth oral administration elimination half-life was 5.27 and 5.39 h; maximum concentration was 74 and 68 ng/mL; time to maximum concentration was 2.67 and 2.33 h; and area under the curve was 713 and 660 hr*ng/mL. Oral bioavailability was determined to be 13.7%. Packed cell volume, hemoglobin, and red blood cell counts were significantly decreased 5 days after the first PO administration, and serum glucose was significantly elevated 5 days after the first PO administration. In conclusion, serum concentrations of prednisolone after IV and PO administration appear to be similar to other veterinary species. Future research will be needed to determine the pharmacodynamics of prednisolone in alpacas.

scholarly journals Effects of Diabetes Mellitus Induced by Alloxan on the Pharmacokinetics of Metformin in Rats: Restoration of Pharmacokinetic Parameters to the Control State by Insulin Treatment

2008 ◽  
Vol 11 (1) ◽  
pp. 88 ◽  
Author(s):  
Myung G. Lee ◽  
Young H Choi ◽  
Inchul Lee
Keyword(s):  
Diabetes Mellitus ◽  
Oral Administration ◽  
Protein Expression ◽  
Intravenous Administration ◽  
Insulin Treatment ◽  
Pharmacokinetic Parameters ◽  
Mrna Levels ◽  
Altered Pharmacokinetic ◽  
Intravenous And Oral Administration ◽  
Control State

To test the effect of insulin treatment on the pharmacokinetics of metformin in rats with diabetes mellitus induced by alloxan (DMIA rats). The following results were reported from other studies. Metformin was metabolized via hepatic CYP2C11, 2D1, and 3A1/2 in rats. In DMIA rats, the protein expression and mRNA levels of hepatic CYP2C11 and 3A1/2 decreased and increased, respectively. In rat model of diabetes mellitus induced by streptozotocin, the protein expression of hepatic CYP2D1 was not changed. The increase in hepatic CYP1A2, 2B1, and 2E1, and decrease in hepatic CYP2C11 in DMIA rats was returned to the controls by insulin treatment. METHODS. Metformin (100 mg/kg) was administered intravenously and orally to the control rats, DMIA rats, and DMIA rats with insulin treatment for 3 weeks (DMIA rats with insulin). RESULTS. After intravenous administration of metformin to the DMIA rats, the CLR and CLNR of the drug were significantly slower than the controls. After oral administration of metformin to the DMIA rats, the AUC of the drug was also significantly greater than the controls. After intravenous administration of metformin to the DMIA rats with insulin, the significantly slower CLNR of the drug in the DMIA rats was returned to the controls. The altered pharmacokinetic indices observed following intravenous and oral administration of metformin to DMIA rats returned to the control values in the DMIA rats with insulin. CONCLUSIONS. The significantly slower CLNR of metformin in the DMIA rats could be due to the decrease in hepatic CYP2C11 than the controls. The comparable CLNR of metformin between the DMIA rats with insulin and the control rats could be due to restoration of hepatic CYP enzyme changes in DMIA rats to the controls.

Nimodipine in the Treatment of Subarachnoid Hemorrhage

DICP ◽  
1989 ◽  
Vol 23 (6) ◽  
pp. 451-455 ◽  
Author(s):  
Sally Usdin Yasuda ◽  
Karen J. Tietze
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Adverse Effects ◽  
Oral Administration ◽  
Calcium Channel Antagonist ◽  
Clinical Studies ◽  
Oral Bioavailability ◽  
Half Life ◽  
Cerebral Blood Vessels ◽  
Vasodilatory Effect ◽  
Intravenous And Oral Administration

Nimodipine, a calcium-channel antagonist with a relatively selective vasodilatory effect on cerebral blood vessels, has recently been approved for improvement of neurologic deficits due to spasm following subarachnoid hemorrhage. Nimodipine has low oral bioavailability (2.7–27.9 percent), a short half-life (2 h), is highly protein bound (98–99 percent), and is hepatically metabolized. Clinical studies have evaluated topical, intravenous, and oral administration of nimodipine for the treatment of cerebral artery spasm associated with subarachnoid hemorrhage. These studies document some benefit of the drug in reducing the occurrence of severe neurologic deficit, although this effect is not universal. Few adverse effects have been noted. Further studies are necessary to evaluate the pharmacologic and pharmacokinetic characteristics, the appropriate dose and route of administration, adverse effects, drug interactions, and the therapeutic efficacy of nimodipine before routine use can be recommended.

scholarly journals Pharmacokinetics of Pantoprazole and Pantoprazole Sulfone in Goats After Intravenous Administration: A Preliminary Report

2021 ◽  
Vol 8 ◽  
Author(s):  
Joe S. Smith ◽  
Jonathan P. Mochel ◽  
Windy M. Soto-Gonzalez ◽  
Rebecca R. Rahn ◽  
Bryanna N. Fayne ◽  
...  
Keyword(s):  
Intravenous Administration ◽  
Half Life ◽  
Plasma Clearance ◽  
Primary Study ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Data ◽  
Study Objective ◽  
Elimination Half Life ◽  
Elimination Half

Background: Ruminant species are at risk of developing abomasal ulceration, but there is a lack of pharmacokinetic data for anti-ulcer therapies, such as the proton pump inhibitor pantoprazole, in goats.Objective: The primary study objective was to estimate the plasma pharmacokinetic parameters for pantoprazole in adult goats after intravenous administration. A secondary objective was to describe the pharmacokinetic parameters for the metabolite, pantoprazole sulfone, in goats.Methods: Pantoprazole was administered intravenously to six adult goats at a dose of 1 mg/kg. Plasma samples were collected over 36h and analyzed via reverse phase high performance liquid chromatography for determination of pantoprazole and pantoprazole sulfone concentrations. Pharmacokinetic parameters were determined by non-compartmental analysis.Results: Plasma clearance, elimination half-life, and volume of distribution of pantoprazole were estimated at 0.345 mL/kg/min, 0.7 h, and 0.9 L/kg, respectively following IV administration. The maximum concentration, elimination half-life and area under the curve of pantoprazole sulfone were estimated at 0.1 μg/mL, 0.8 h, and 0.2 hr*μg/mL, respectively. The global extraction ratio was estimated 0.00795 ± 0.00138. All animals had normal physical examinations after conclusion of the study.Conclusion: The reported plasma clearance for pantoprazole is lower than reported for foals, calves, and alpacas. The elimination half-life appears to be < that reported for foals and calves. Future pharmacodynamic studies are necessary for determination of the efficacy of pantoprazole on acid suppression in goats.

scholarly journals Pharmacokinetics of Salicylic Acid Following Intravenous and Oral Administration of Sodium Salicylate in Sheep

2018 ◽  
Author(s):  
Shashwati Mathurkar ◽  
Preet Singh ◽  
Kavitha Kongara ◽  
Paul Chambers
Keyword(s):  
Salicylic Acid ◽  
Oral Administration ◽  
High Performance ◽  
Sodium Salicylate ◽  
Elimination Half ◽  
Healthy Sheep ◽  
Array Detection ◽  
Intravenous And Oral Administration ◽  
Effective Plasma Concentration ◽  
Different Doses

The pharmacokinetics of salicylic acid (SA) in sheep was evaluated following intravenous (IV) and oral administration of sodium salicylate (sodium salt of salicylic acid) at different doses. Six healthy sheep were administered sodium salicylate (SS) IV at doses of 10, 50, 100 and 200 mg/kg body weight and another six sheep were drenched with 100 and 200 mg/kg of SS orally. Both studies were randomised crossover trials. A one-week washout period between each treatment was allowed in both studies. Blood samples were collected at 0, 15, 30 minutes and 1, 2, 4 and 6 hours after IV and oral SS administrations. Plasma SA concentrations were determined using high performance liquid chromatography with diode array detection method. Pharmacokinetic variables were calculated in a non-compartmental model. The elimination half-life (T1/2 el) of SA after IV administration of 200 mg/kg SS was 1.16 ± 0.32 hours. Mean bioavailability of SA was 64%, and mean T1/2 el was 1.90 ± 0.35 hours, after 200 mg/kg of oral SS. The minimum plasma SA concentration (16.8 µg/mL) required to produce analgesia in humans was achieved after IV administration of 100 and 200 mg/kg SS in sheep for about 0.17 hour in this study. Experiments on pharmacokinetic-pharmacodynamics modelling are required to determine the actual effective plasma concentration range of SA in sheep.

scholarly journals Flucloxacillin bone and soft tissue concentrations assessed by microdialysis in pigs after intravenous and oral administration

2021 ◽  
Vol 10 (1) ◽  
pp. 60-67
Author(s):  
Mathias A. F. Bendtsen ◽  
Mats Bue ◽  
Pelle Hanberg ◽  
Josefine Slater ◽  
Maja B. Thomassen ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Oral Administration ◽  
Cortical Bone ◽  
Bone Tissue ◽  
Intravenous Administration ◽  
Antimicrobial Prophylaxis ◽  
Subcutaneous Tissue ◽  
Group Iv ◽  
Continuous Administration ◽  
Intravenous And Oral Administration

Aims Flucloxacillin is commonly administered intravenously for perioperative antimicrobial prophylaxis, while oral administration is typical for prophylaxis following smaller traumatic wounds. We assessed the time, for which the free flucloxacillin concentration was maintained above the minimum inhibitory concentration ( fT > MIC) for methicillin-susceptible Staphylococcus aureus in soft and bone tissue, after intravenous and oral administration, using microdialysis in a porcine model. Methods A total of 16 pigs were randomly allocated to either intravenous (Group IV) or oral (Group PO) flucloxacillin 1 g every six hours during a 24-hour period. Microdialysis was used for sampling in cancellous and cortical bone, subcutaneous tissue, and the knee joint. In addition, plasma was sampled. The flucloxacillin fT > MIC was evaluated using a low MIC target (0.5 μg/ml) and a high MIC target (2.0 μg/ml). Results Intravenous administration resulted in longer fT > MIC (0.5 μg/ml) compared to oral administration, except for cortical bone. In Group IV, all pigs reached a concentration of 0.5 μg/ml in all compartments. The mean fT > MIC (0.5 μg/ml) was 149 minutes (95% confidence interval (CI) 119 to 179; range 68 to 323) in subcutaneous tissue and 61 minutes (95% CI 29 to 94; range 0 to 121) to 106 minutes (95% CI 76 to 136; range 71 to 154) in bone tissue. In Group PO, 0/8 pigs reached a concentration of 0.5 μg/ml in all compartments. For the high MIC target (2.0 μg/ml), fT > MIC was close to zero minutes in both groups across compartments. Conclusion Although intravenous administration of flucloxacillin 1 g provided higher fT > MIC for the low MIC target compared to oral administration, concentrations were surprisingly low, particularly for bone tissue. Achievement of sufficient bone and soft tissue flucloxacillin concentrations may require a dose increase or continuous administration. Cite this article: Bone Joint Res 2021;10(1):60–67.

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