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Check out this AE half-life profile of various drugs
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The Iron Game
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mrt said:
in ovulating women? cause to my knowledge no studies done on this on men on test replacement therapy.
Panerai. Maybe nitty picky but an extra day is a lot. It went from 4- 5 days up to 6, so as I suggested it is closer to enanthate than prop.
Peace
NubianBeauty
Banned
^
mrt
New member
The Iron Game said:
Iron Game,
are you sure that half life of drugs depend on the sex? Yes, Arimidex is a drug for women, but it shouldn't have a different half life in men(IMHO) 40-50 hours half life is mentioned in that little leaflet of a original Zeneca Arimidex.
BTW, they mention a test on healthy men only for overdose effects. They gave them one dosage of 60 (Sixty) mg and it was tolerated well with not many serious sides
ANABOLICchild
New member
bamp to dat yo boyeeeeeeeeeeeeeee!
I should start putting my juice where my mouth is.
I should start putting my juice where my mouth is.
1: Int J Androl 1984 Jun;7(3):181-7 Related Articles, Books
Comparative pharmacokinetics of testosterone enanthate and testosterone cyclohexanecarboxylate as assessed by serum and salivary testosterone levels in normal men.
Schurmeyer T, Nieschlag E.
The pharmacokinetics of 2 testosterone esters, testosterone enanthate and testosterone cyclohexanecarboxylate, were compared in a single blind crossover study in healthy young men. Their effects on serum and salivary levels of testosterone, as well as on the serum levels of LH, FSH and prolactin were measured after the injection of doses equivalent to 140 mg free testosterone. Both preparations yielded supraphysiological testosterone levels in serum and saliva as early as 2 h following injection, reaching peak levels 4 to 5 times above basal between 8 and 24 h. LH and FSH levels were suppressed as long as serum testosterone levels were elevated. Nine days after injecting testosterone enanthate and 7 days after giving testosterone cyclohexanecarboxylate, serum and salivary levels of testosterone had returned to basal. The longer activity of testosterone enanthate was also evidenced from more extended suppression of gonadotrophin levels. Although neither preparation is ideal because of the initial supraphysiological peaks, testosterone enanthate appears preferable for clinical use because of its slightly longer duration of action.
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Very interesting. According to this study, half life of Enanthate is 4.5 days, and accoring to the one on Nandolones, PhenylProp's is 6.5 days.
May be GymRatSD is right, and PP's half life is longer then Enanthate, and my assumption that addition of benzene ring is ineffective for prolonging half life of steroid is wrong.
Comparative pharmacokinetics of testosterone enanthate and testosterone cyclohexanecarboxylate as assessed by serum and salivary testosterone levels in normal men.
Schurmeyer T, Nieschlag E.
The pharmacokinetics of 2 testosterone esters, testosterone enanthate and testosterone cyclohexanecarboxylate, were compared in a single blind crossover study in healthy young men. Their effects on serum and salivary levels of testosterone, as well as on the serum levels of LH, FSH and prolactin were measured after the injection of doses equivalent to 140 mg free testosterone. Both preparations yielded supraphysiological testosterone levels in serum and saliva as early as 2 h following injection, reaching peak levels 4 to 5 times above basal between 8 and 24 h. LH and FSH levels were suppressed as long as serum testosterone levels were elevated. Nine days after injecting testosterone enanthate and 7 days after giving testosterone cyclohexanecarboxylate, serum and salivary levels of testosterone had returned to basal. The longer activity of testosterone enanthate was also evidenced from more extended suppression of gonadotrophin levels. Although neither preparation is ideal because of the initial supraphysiological peaks, testosterone enanthate appears preferable for clinical use because of its slightly longer duration of action.
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Very interesting. According to this study, half life of Enanthate is 4.5 days, and accoring to the one on Nandolones, PhenylProp's is 6.5 days.
May be GymRatSD is right, and PP's half life is longer then Enanthate, and my assumption that addition of benzene ring is ineffective for prolonging half life of steroid is wrong.
1: Acta Endocrinol Suppl (Copenh) 1985;271:19-30 Related Articles, Books
Pharmacokinetic parameters of nandrolone (19-nortestosterone) after intramuscular administration of nandrolone decanoate (Deca-Durabolin) to healthy volunteers.
Wijnand HP, Bosch AM, Donker CW.
Nandrolone decanoate (Deca-Durabolin) was injected intramuscularly into healthy volunteers. One group of females received one injection of 100 mg and three groups of males received one injection of 200 mg, two repeat injections of 100 mg or four repeat injections of 50 mg respectively. The serum levels of nandrolone (19-nortestosterone) were determined by radioimmunoassay and used to estimate pharmacokinetic parameters. The following pharmacokinetic parameters were found: a mean half-life of 6 days for the release of the ester from the muscular injection depot into the general circulation; a mean half-life of 4.3 h for the combined processes of hydrolysis of nandrolone decanoate and of distribution and elimination of nandrolone; a mean nandrolone serum clearance of 1.55 1 X h-1 X kg-1. The half-life of hydrolysis of nandrolone decanoate in serum was of the order of one hour or less. The data are consistent with linear kinetics.
PMID: 3865478 [PubMed - indexed for MEDLINE]
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Ha???? Now, according to this one, Decanoate's half life is 6.5 days also. WTF??????
In study on Nandrolones( Decanoate and PP) plasma concentration reterned to normal in 13 days for PP, and 20 days for Decanoate, which gives 10 days half life for Decanoate.
Very inconclusive data!
Some good explanation on how ester work from Nandrolone study:
"). Experimental studies suggest that absorption rates are predicted by the oil/water partition coefficients (or hydrophobicity) and that the oil vehicle is absorbed more slowly than the androgen ester (Tanaka et al., 1974 ). In humans, the very short propionate (three-carbon aliphatic) ester of testosterone has distinctly shorter duration of action than esters with longer (seven- or eight-carbon) side-chains (Nieschlag et al., 1976 ; Schulte-Beerbuhl and Nieschlag, 1980 ; Schurmeyer and Nieschlag, 1984 ; Belkien et al., 1985 ; Fujioka et al., 1986 ). More subtle changes in side-chain ester structure have proven ineffective in altering human clinical pharmacokinetics, because substitution of a linear aliphatic side-chain of seven carbons (enanthate) with either a saturated, cyclized, seven-carbon aliphatic chain (cyclohexanecarboxylate) (Schurmeyer and Nieschlag, 1984 ) or a linear, aliphatic, eight-carbon chain (cypionate) (Schulte-Beerbuhl and Nieschlag, 1980 ) resulted in virtually unchanged kinetics. Wider variation in ester side-chain chemistry to include greater chain length and/or aromatic ring structures is a more effective determinant of ester pharmacokinetics, because nandrolone hexoxyphenylpropionate ester (aromatic ring with 18 carbons) had far better depot properties, with a prolonged and retarded release profile, compared with the decanoate (aliphatic chain with 10 carbons) (Belkien et al., 1985 ). The present study indicates that a side-chain ester consisting of a 10-carbon aliphatic chain(Decanoate) has better depot properties than a nine-carbon chain including an aromatic ring(Phenylpropionate)."
Pharmacokinetic parameters of nandrolone (19-nortestosterone) after intramuscular administration of nandrolone decanoate (Deca-Durabolin) to healthy volunteers.
Wijnand HP, Bosch AM, Donker CW.
Nandrolone decanoate (Deca-Durabolin) was injected intramuscularly into healthy volunteers. One group of females received one injection of 100 mg and three groups of males received one injection of 200 mg, two repeat injections of 100 mg or four repeat injections of 50 mg respectively. The serum levels of nandrolone (19-nortestosterone) were determined by radioimmunoassay and used to estimate pharmacokinetic parameters. The following pharmacokinetic parameters were found: a mean half-life of 6 days for the release of the ester from the muscular injection depot into the general circulation; a mean half-life of 4.3 h for the combined processes of hydrolysis of nandrolone decanoate and of distribution and elimination of nandrolone; a mean nandrolone serum clearance of 1.55 1 X h-1 X kg-1. The half-life of hydrolysis of nandrolone decanoate in serum was of the order of one hour or less. The data are consistent with linear kinetics.
PMID: 3865478 [PubMed - indexed for MEDLINE]
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Ha???? Now, according to this one, Decanoate's half life is 6.5 days also. WTF??????
In study on Nandrolones( Decanoate and PP) plasma concentration reterned to normal in 13 days for PP, and 20 days for Decanoate, which gives 10 days half life for Decanoate.
Very inconclusive data!
Some good explanation on how ester work from Nandrolone study:
"). Experimental studies suggest that absorption rates are predicted by the oil/water partition coefficients (or hydrophobicity) and that the oil vehicle is absorbed more slowly than the androgen ester (Tanaka et al., 1974 ). In humans, the very short propionate (three-carbon aliphatic) ester of testosterone has distinctly shorter duration of action than esters with longer (seven- or eight-carbon) side-chains (Nieschlag et al., 1976 ; Schulte-Beerbuhl and Nieschlag, 1980 ; Schurmeyer and Nieschlag, 1984 ; Belkien et al., 1985 ; Fujioka et al., 1986 ). More subtle changes in side-chain ester structure have proven ineffective in altering human clinical pharmacokinetics, because substitution of a linear aliphatic side-chain of seven carbons (enanthate) with either a saturated, cyclized, seven-carbon aliphatic chain (cyclohexanecarboxylate) (Schurmeyer and Nieschlag, 1984 ) or a linear, aliphatic, eight-carbon chain (cypionate) (Schulte-Beerbuhl and Nieschlag, 1980 ) resulted in virtually unchanged kinetics. Wider variation in ester side-chain chemistry to include greater chain length and/or aromatic ring structures is a more effective determinant of ester pharmacokinetics, because nandrolone hexoxyphenylpropionate ester (aromatic ring with 18 carbons) had far better depot properties, with a prolonged and retarded release profile, compared with the decanoate (aliphatic chain with 10 carbons) (Belkien et al., 1985 ). The present study indicates that a side-chain ester consisting of a 10-carbon aliphatic chain(Decanoate) has better depot properties than a nine-carbon chain including an aromatic ring(Phenylpropionate)."
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