Means to enhance absorption of Doxycycline and other means to enhance CAP
As a CAP for Cpn is to be maintained over many months, the abx can pose a problem to organs like liver and kidneys, as those are part of the elimination route. Higher doses also carry a higher risk of other side-effects. Hence, enhancing the effect of abx taken is beneficial.
FIR sauna has been discussed, and in Lyme, even small increases of temperature multiplies the effect of investigated abx (ceftriaxone: MIC one eitght; penicillin: MIC one sixteenth, when temp increases from 36C to 38C). [Reisinger et al: Antibiotics and Increased Temperature against Borrelia burgdorferi In Vitro; Scand J Infect Dis 28: 155 157, I996] As far as I understand,all forms of body temperature rise may be beneficial, also warm/hot baths as well as exercising. The question is if there is a similar effect for Cpn.
Tetracycline has been mentioned as being less absorbed when taken with food, especially milk and realted products, whereas doxycycline is thought not to be affected similarly. However, in one study the picture isn't as clear in my view. Even if the drop in serum concentration for Tetracycline if taken with food was considerable (about 40%, worse with food containing protein), the similar drop for Doxycycline was about 28%. Converesely, one can enhance serum concentration towards 40% by taking it on emtpy stomach. Like taking 140mg instead of 100mg (I've done this first with Doxy, then with Mino; minimal gut reactions from Doxy none from Mino). [Welling et al: Bioavailability of Tetracycline and Doxycycline in Fasted and Nonfasted Subjects; ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, Mar. 1977, p. 462-469]
There are similar results for physical activity after taking abx, and even if some of the effect of increased plasma levels are from reduced excretion and reduced intercellular plasma volume, not all is. Some seems to come from enhanced absorption. Peak serum concentration 6.5 μg for exercise vs 4.8 μg for rest, and similar for the serum level time integral 106 vs 81 μgh/ml. [Ylitalo: Effect of Exercise on the Serum Level and Urinary Excretion of Tetracycline, Doxycycline and Sulphamethizole; Europ. J. clin. Pharmacol. 12, 367-373, 1977]
Most likely some of the effects are overlapping, but taking abx a few hours after the last meal and then exercising a bit as possible followed by sauna or a hot tub or alternating the last measures (exercise and sauna/hot tub) may be a good way to boost a CAP. Then there is the question if these effects are present in other abx, both from the same class (like Minocycline which I am currently taking), and from other classes (I saw it mentioned that Azithromycin is thought to be absorbed better on empty stomach, e. g., no reference, though)?
On top of these measures to enhance the uptake and effect of abx, there is the wide range of nutrition and supplements to enhance the CAP. In all, the difference between a CAP employed in different ways can be considerable.
THe problem is to get everything together, to sort out the relative importance of different measures. From reports here in the forum, the blogs etc, it is also obvious that the effects differ between persons.