The Mass Patch works on the stimulation of the glands to produce more androgenic responses in your body. It works to elevate and not surpass your natural body level.
Hormone Replacement Therapy is an artificial injection of hormones into the body to replace what the body is not producing. This can oftentimes shut down the production completely in some cases. Making the person reliant on this for normal levels.
Hence the Mass Patch can be used together. But the best results may be in post cycles of the HRT to help stimulate your own body production again.
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