You should know that the grapefruit juice extract in the AM is significantly reducing the rate of metabolism (increasing the half life) of the superdrol. So you're going to find that the results from lower mg dosages will mimic higher dosages due to this phenomenon. James Maskalyk wrote an article about how the CYP3A4 molecule, which assists in the metabolism of anabolic steroids, is interfered with by grapefruit, which is why PP includes it in AM. Based on that I can tell you that I personally wouldn't go to 30mg SD in your current cycle. Not something to worry about as much as be mindful of.
Here's another article I found, though it is obviously not published in a journal.
The Effect of Grapefruit Juice on Methylated (Pro)Hormones! by Designer Supps
GRAPEFRUIT JUICE AND DRUGS
HOW DOES
GRAPEFRUIT JUICE AFFECT THE DRUGS I AM TAKING?
Grapefruit juice blocks
cytochrome P-450 3A4 and Ia2 (CYP3A4 and CYP1A2) enzymes in your intestinal
wall. Common to all living organisms, the body has evolved the cytochrome P-450
system, a superfamily of enzymes responsible for removing drugs and toxins from
the body. The cytochrome P-450 3A4 subfamily, located predominantly in the liver
and intestinal tract, is one of the most common enzyme systems for metabolizing
drugs. Most drugs are lipid-soluble or"fat-loving", so that they are readily
absorbed in your bloodstream. To eliminate these drugs, however, in the
cytochrome P450 system either breaks them down in the gut or changes them in to
a more water-soluble or "water-loving" version in the liver. The kidney can then
eliminate them in the urine. Thus, the liver,gut, and kidney work together to
prevent excessive amounts of drug and/or toxins from getting in to your
bloodstream. Grapefruit juice blocks the cytochrome P450 3A4 enzyme systems in
your gut. By inhibiting this defence mechanism, grapefruit juice may increase
the blood levels of some drugs. Therefore, you may experience adverse effects
from the drugs you are taking when taken with grapefruit juice.
WHICH
SUBSTANCE IN THE GRAPEFRUIT JUICE IS RESPONSIBLE FOR THESE INTERACTIONS WITH
DRUGS?
The precise chemical nature of the substance in the grapefruit
juice that inhibits gut wall CTP 3A4 enzymes is unknown. It has been suggested
that flavanoids, coumarin, or psoralen derivatives in the grapefruit juice could
be the inhibitors. The amount of inhibiting substance in grapefruit juice may
vary by brand, concentrations and storage conditions.
I DRINK ONE GLASS
OF REGULAR GRAPEFRUIT JUICE WITH BREAKFAST IN THE MORNING, WILL THIS AFFECT THE
DRUGS I AM TAKING?
Yes. Regular grapefruit juice is prepared by diluting
frozen grapefruit juice with normal amount of water. Double-strength grapefruit
juice is prepared by diluting frozen grapefruit juice with half the normal
amount of water. One glass of regular grapefruit juice is enough to
significantly raise the blood levels of the number of drugs.
FOR HOW LONG
DOES THE GRAPEFRUIT JUICE INHIBIT CYP 3A4?
The inhibitory effect of
grapefruit juice on CYP 3A4 can last for several hours. A recent study found
increased blood levels of calcium-channel blocker felodipine (Plendil) even when
the drug was given 24 hours after drinking grapefruit juice.
I TAKE AN
EXTENDED RELEASE PRODUCT, IS THIS ALSO AFFECTED BY GRAPEFRUIT JUICE?
Yes.
Grapefruit juice increases the blood levels of extended release preparations.
Recent studies have shown increased blood levels of extended release
felodipine,extended release nifedipine (Adalat, Procardia) when taken with
grapefruit juice.
WHICH DRUGS ARE AFFECTED BY GRAPEFRUIT JUICE AND WHAT
HAPPENS WHEN THEIR BLOOD LEVELS INCREASE?
CYP 3A4 is involved in the
metabolism of many medications. When CYP 3A4 is inhibited by grapefruit juice,
the blood levels of many medications may rise. Examples of drugs reported to
interact are listed in the table below. Since many more drugs are likely to
interact, it is important to ask your doctor or pharmacist if you drink
grapefruit juice and are taking any medications.
