T Nation

What's the Best Time to Take an AI?


I know there is no right or wrong answer to this but I found myself wondering during my cardio today...is there a point in the day when an AI is more effective or better suited to do it's job?

Test levels peak during deep sleep, so would it be wrong to assume that more aromatization occurs upon waking? Would it be better to take your AI first thing on an empty stomach, or do you take it right before bed?

Basically, when do you guys take your AI, and why?


AI's have half lives. Dose it accordingly. Convenience would be the second factor.

JMO. Not musch science involved but that has worked for me.


I take mine in the morning, more for convenience than anything. In the morning I have to take my medicines, so I'll remember. Who knows what time I'll go to bed, I'm likely to forget. I can't even remember to take ZMA most of the time.


i just take it with my injection. Can't forget than.


IME estrogen rises much more at night, after 7pm or so.. i find gyno aggrevates leter in the day, in the early evening.

I believe it is due to the fact that Test levels are highest in the morning, and by the evening they have dropped resulting in a slight shift in testosterone/estrogen balances - favouring estrogen slightly.



this was my thinking as well. I figure that taking the AI upon waking when test levels had just been at their peak would blunt the aromatization that would follow as the day progressed.


I not only agree, but follow this practice too.



I never really thought about why, but I take mine in the am with my morning juice.

just a habit I came into of taking oral meds in the am and then I inject at night shower and go to bed.

but I do have to say I feel better when I take it in the am, I just feel slightly off if i miss a day or if I take it in the evenings
really cant explain how I feel, its not a huge difference not like normal "side effects" but it is a general icky feeling that starts up.


so then the next obvious question would be are you injecting at night to take advantage of your natural peak test levels and absorption or would it be any different to inject in the morning to possibly keep your levels higher through the day? (yes I understand the concept of diffusion through tissues and that an injection does not lead to an immediate boost in test levels)


honestly its not so much to take advantage of the test levels at night, because if you really think about it,my natural production is shut down, meaning there will be spikes only after the bolus starts to diffuse through the muscle the natural test spikes really wont apply here all that much.

its just a habbit, when I first started prop along time ago I got slight itchiness and soreness after so many mls, usually about 2-3mls is when I would "hurt"
running really hot water over the site really seems to help with that, I never have any soreness anymore.

also its not always before I shower sometimes its after just for cleanliness.

if you inject often you wont have to worry about diffusion rates or any of that because after you start its kind of like a cascading effect and you will always have a constant level of hormones in your system.

my opinion is that it really dosent mater when you take your meds just if you take them often enough not to be spiking your system too bad.

it may mater but very minimally.


thanks for the replies maddy, very helpful stuff.

still interested in hearing what some of you other vets have to say


I think you have your answer - with all drugs that have a long half life that eventually achieve peak and stable blood levels, such as letrozole (after 6 weeks), it doesnt matter really.

AI's to my knowledge, arimidex and letrozole (i am not versed well with exemestane) both have a relatively long half life - for the types of oral drugs we use at least - over 3 days, meaning you get that 'knock on effect' that maddy spoke of where levels build to a peak and stable state.

Take into account the fact that NATURAL test often is higher in the morning, rising one's levels of aromatase, coupled with the fact that even after over a year of suppression (and testosterone supplementation) i STILL noticed my gyno would aggrevate in the evening... and you may want to dose in the AM.

I personally would, and have - but i honestly think dosing in the evening is fine too.

It is a bit of a weak, non-important question. Just take it and take it regularly, and you will be fine as long as dosages of AI to Aromatase are managed (increasing AI with increasing dose of aromatizable androgens) along with the type of AI being considered for your health and drug needs.