Trough Levels - Propionate vs Cypionate - Graph results?

[S1W]

I created the plots below using a tool from another site, which I'm sure many of you have seen before. I'd like some clarification as to whether or not the way I'm interpreting the data is correct.

I'm aware of the ester weight/percentage for the two esters being compared, and that 120mg cyp nets out to about 84mg/week vs 119mg prop nets out to about 100mg/week.

Here are graphs comparing the "release" of each protocol over 8 weeks:

60mg E3.5D Cypionate (120mg/week)

17mg/day Propionate (119mg/week)

In the first graph (cypionate), after levels have stabilized the peak levels are 14.91, trough at 9.84.

In the second graph (propionate), after levels have stabilized the peak levels are 20.32, trough at 13.18.

I realize that there are other factors that might affect "release", but I would take the data above to be an approximation of expected results.

Which brings me to my main question: I would have expected the trough on the daily propionate to be lower than the trough on the E3.5D cypionate. The graphs suggest otherwise. What, if anything, am I missing?

Is it correct that when comparing the two protocols, the propionate protocol will in general provide higher levels across the board?

 

[Cataceous]

It is in part a result of using more testosterone for propionate, which raises all those values, including the troughs. The daily dose of propionate should be more like 14 mg to match 60 mg E3.5D of cypionate. Even with this correction there is still some problem with the plotter; 14 mg propionate should yield an average release of 11.2 mg testosterone per day using their—incorrect—figure of 80% testosterone content. Instead, on the graph it looks closer to 14 mg.

In any case, the main question relates to how the injection interval compares to the drug half-life. It is this ratio that determines how much variation there is in released testosterone over the injection interval. The greater this ratio the greater the swing. In your example the ratio for propionate is 1 day / 0.8 days = 1.25. The ratio for cypionate is 3.5 days / 5 days = 0.70. So the bigger swing is indeed expected with propionate—higher peaks and lower troughs, same average at same T dose. If you took the injection interval for cypionate up to a week then cypionate would have greater variation: 7 days / 5 days = 1.40.

If you're looking for a blanket statement: In comparing propionate to any ester with a longer half-life, if the same injection interval and same total dose of testosterone are used then propionate will always create higher peaks and lower troughs in serum testosterone.

 

[S1W]

Thank you - always learning from you.

You may have addressed this in your first paragraph, but in case I misunderstood: given the examples I outlined - 60mg E3.5D Cyp vs 17mg day Prop - would you expect that trough levels would be higher on the prop protocol?

 

[Cataceous]

Ok, 60 mg E3.5D TC releases 12 mg T per day at steady state. The 17 mg ED TP releases 14.2 mg T per day. To do the exact calculations requires some assumptions, so be aware that different results are possible.

For simplicity I'll assume the post-injection time to peak release is negligible. Additionally, I'll model the exponential decay as a linear drop. For TP, one day with a 0.8 day half-life leads to a decline of 58% from the peak. The assumption of linearity makes things easy: Peak * 0.71 = average = 14.2 mg. Therefore the peak release is 20 mg. And Trough = Peak * 0.42, so Trough = 8.4 mg.

For TC, 3.5 days with a 5 day half-life is a decline 38% from the peak. Peak * 0.81 = average = 12 mg. Peak release then is 14.9 mg. Trough = Peak * 0.62 = 9.1 mg.

Because the difference in trough values is less than one milligram I would call it nearly a tie.