you only need 1 or the other, not both
I highly disagree. It is most efficient to take both.
Nolva and Clomid are different in terms of which selective tissues they bind to, which also means it affects the upstart of your system differently.
Clomid is selective to the suprapituitary; while Nolva is selective to breast, bone, and liver ERs.
In studies showing levels of LH, FSH, and testosterone checked after short durations of Nolva, they were either insignificant or their was an actual drop. I believe this is because Nolva selectively works at the mammary (as well as bone and liver), thus taking longer for LH stimulation to occur.
With Clomid, benefits to gonadotrophin concentrations, LH, FSH, and serum testosterone levels can be seen in short periods of 2-6 weeks. Because of the apparent selective nature of the two, and given the usual PCT duration, Clomid is by far superior at LH stimulation than Nolva. In laymans terms, that basically means Clomid is quicker at bringing your balls back and producing natural testosterone. So if you were to only run either Clomid or Nolva, choose Clomid.
However, both is the wise choice for a couple of reasons:
1. Nolva acts as the preventive measure to the estrogen flux
occurred post-cycle while Clomid is the primary LH stimulator(Even more so in the case an AI is not used). In a sense, the Nolva blocks the estrogen from binding to receptors, while Clomid kickstarts the LH.
2. If you're running a longer PCT, Clomid needs to be discontinued after a while as it has been shown to desensitize GnRH, this is due, IMO, to it's selective nature to the suprapituitary. In the longer periods of PCT, the Clomid will be phased out, leaving Nolva and Arimidex.
