Mauritio
Member
- Joined
- Feb 26, 2018
- Messages
- 5,669
So @haidut said on the recent podcast with danny roddy that there was some evidence that clonidine lowers prolactin. I was surprised since Prolactin and estrogen are normally so closely tied together and someone posted a study about clonidin increasing estrogen .
I have gone through some studies and found conflicting informations.
For example the human studies show mostly no effect on prolactin.
Whereas in one of the mouse studies there was a very specific dose dependent action where high dose didnt and lower dose did lower prolactin .
All studies that I looked at showed either a reduction or no effect on prolactin ,so I suspect its very safe to take clonidine ( at least from a prolactin standpoint) .
One ting that does concern me is that almost all studie I found that clonidine significantly increases GH. Has anybody any info on what that would mean or how that could be antagonized?
Human studies :
Evaluation of the of Alpha2-Adrenergic Receptors Stimulation Effect on Prolactin Secretion, Based on the Result of the Test with Clonidine Used in the Diagnosis of Children with Short Stature | ESPE2019
The dosage was 200-300mcg
"Short-term adrenergic stimulation of alpha2-receptors (after oral clonidine administration) does not appear to affect Prl secretion in children with short stature in both the ISS and GHD groups."
Effects of clonidine on blood pressure, noradrenaline, cortisol, growth hormone, and prolactin plasma levels in high and low intestinal tone subjects - PubMed - NCBI
The dosage was about 200-250mcg
"...furthermore, a slight but significant reduction of PRL was registered in high IT group"
Only Group to find a significant decrease was high intenstinal tone group (whatever that means?)
Interactions of sleep and clonidine on daytime prolactin secretion in humans. - PubMed - NCBI
The results suggest that alpha 2-adrenergic stimulation does not have a significant role in modulating human PRL secretion during sleep.
Effect of clonidine on growth hormone, prolactin, luteinizing hormone, follicle-stimulating hormone, and thyroid-stimulating hormone in the serum of ... - PubMed - NCBI
The dosage was 6 ng/ml . Dont know how to convert to mg/kg.
"Clonidine had no effect on serum prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), or thyroid-stimulating hormone (TSH)."
Animal Studies:
Alpha-2-adrenergic control of prolactin release. - PubMed - NCBI
This one is really interesting. It did find a dose dependent effect of PRL stiulation in rats. Human equivalent doses of about 750mcg and 3000mcg (hugh doses already) were able to supress PRL ,whereas 15 000mcg did not supress prolactin. Sadly they didnt look at lower doses that translate to usual human doses like 100-200mcg , but since the ability not to supress prolactin only began at really high doses i suspect lower doses should either not effect prolactin or lower it .
"Clonidine alone at doses of 0.05 and 0.2 mg/kg again significantly suppressed prolactin levels, while a dose of 1.0 mg/kg did not (failure of high dose clonidine to suppress prolactin levels suggests an additional effect of clonidine on prolactin secretion unrelated to alpha 2-adrenergic agonist action). All three doses of clonidine completely reversed yohimbine-induced prolactin release."
Inverse control of growth hormone and prolactin secretion in clonidine-stimulated dairy cattle. - PubMed - NCBI
I dont know how to convert cow doses to HED, but they have a bigger body surface , so I suspect HEDs of about 600mcgs- 3000mcgs
An i.v. infusion of 10 micrograms/kg body weight induced GH release to a peak concentration after 30-60 min, while 2 micrograms/kg had no effect on GH secretory patterns. Plasma PRL decreased significantly (P < 0.01) starting 15-60 min after both doses of clonidine, this effect lasting up to 6 h. Clonidine significantly lowered plasma insulin (P < 0.01) and raised plasma glucose (P < 0.01). The changes in plasma GH, PRL, insulin and glucose differed significantly between doses, the 10 micrograms/kg dose being more effective (P < 0.01).
I have gone through some studies and found conflicting informations.
For example the human studies show mostly no effect on prolactin.
Whereas in one of the mouse studies there was a very specific dose dependent action where high dose didnt and lower dose did lower prolactin .
All studies that I looked at showed either a reduction or no effect on prolactin ,so I suspect its very safe to take clonidine ( at least from a prolactin standpoint) .
One ting that does concern me is that almost all studie I found that clonidine significantly increases GH. Has anybody any info on what that would mean or how that could be antagonized?
Human studies :
Evaluation of the of Alpha2-Adrenergic Receptors Stimulation Effect on Prolactin Secretion, Based on the Result of the Test with Clonidine Used in the Diagnosis of Children with Short Stature | ESPE2019
The dosage was 200-300mcg
"Short-term adrenergic stimulation of alpha2-receptors (after oral clonidine administration) does not appear to affect Prl secretion in children with short stature in both the ISS and GHD groups."
Effects of clonidine on blood pressure, noradrenaline, cortisol, growth hormone, and prolactin plasma levels in high and low intestinal tone subjects - PubMed - NCBI
The dosage was about 200-250mcg
"...furthermore, a slight but significant reduction of PRL was registered in high IT group"
Only Group to find a significant decrease was high intenstinal tone group (whatever that means?)
Interactions of sleep and clonidine on daytime prolactin secretion in humans. - PubMed - NCBI
The results suggest that alpha 2-adrenergic stimulation does not have a significant role in modulating human PRL secretion during sleep.
Effect of clonidine on growth hormone, prolactin, luteinizing hormone, follicle-stimulating hormone, and thyroid-stimulating hormone in the serum of ... - PubMed - NCBI
The dosage was 6 ng/ml . Dont know how to convert to mg/kg.
"Clonidine had no effect on serum prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), or thyroid-stimulating hormone (TSH)."
Animal Studies:
Alpha-2-adrenergic control of prolactin release. - PubMed - NCBI
This one is really interesting. It did find a dose dependent effect of PRL stiulation in rats. Human equivalent doses of about 750mcg and 3000mcg (hugh doses already) were able to supress PRL ,whereas 15 000mcg did not supress prolactin. Sadly they didnt look at lower doses that translate to usual human doses like 100-200mcg , but since the ability not to supress prolactin only began at really high doses i suspect lower doses should either not effect prolactin or lower it .
"Clonidine alone at doses of 0.05 and 0.2 mg/kg again significantly suppressed prolactin levels, while a dose of 1.0 mg/kg did not (failure of high dose clonidine to suppress prolactin levels suggests an additional effect of clonidine on prolactin secretion unrelated to alpha 2-adrenergic agonist action). All three doses of clonidine completely reversed yohimbine-induced prolactin release."
Inverse control of growth hormone and prolactin secretion in clonidine-stimulated dairy cattle. - PubMed - NCBI
I dont know how to convert cow doses to HED, but they have a bigger body surface , so I suspect HEDs of about 600mcgs- 3000mcgs
An i.v. infusion of 10 micrograms/kg body weight induced GH release to a peak concentration after 30-60 min, while 2 micrograms/kg had no effect on GH secretory patterns. Plasma PRL decreased significantly (P < 0.01) starting 15-60 min after both doses of clonidine, this effect lasting up to 6 h. Clonidine significantly lowered plasma insulin (P < 0.01) and raised plasma glucose (P < 0.01). The changes in plasma GH, PRL, insulin and glucose differed significantly between doses, the 10 micrograms/kg dose being more effective (P < 0.01).
