These are not a singular thing. You actually have several separate issues going on.
Symptoms:
~Complete & Utter inability to gain weight or muscle
There are several possibilities here so I would focus on the known problems first, especially since so many things are interconnected.
~Hives on skin when scratched
This is called geographic dermatitis, and is associated with weak adrenal glands. Here is information on the adrenals:
http://curezone.com/forums/fm.asp?i=1527351#i
~Loss of skin pigmentation (small patch)
This could be vitiligo, which is also associated with weak adrenals leading to autoimmunity.
~Dry Hair
~Dry Skin
These are typical symptoms of hypothyroidism, which can occur from a long list of reasons including adrenal dysfunction. It can also occur from low iodine, hormone issues, chlorine, fluoride or bromine exposure, high rT3, poor T4 to T3 conversion, hypothalamus or pituitary problems, etc. The best way to determine if the thyroid is low is with basal body temperature:
http://curezone.com/forums/fm.asp?i=1446516#i
~Acne, utmost certainty triggered by any sexual activity; loss of vitamins?
Information on acne:
http://curezone.com/forums/fm.asp?i=1575143#i
~Stomach/Intestinal general area pain
Again this could have a number of reasons. Lack of stomach acid and flora is the most common reasons for gastrointestinal issues. Do you get a lot of bloating as well and possibly acid reflux?
http://curezone.com/forums/fm.asp?i=1581539#i
http://curezone.com/forums/fm.asp?i=1480855#i
http://curezone.com/forums/fm.asp?i=1491685#i
~Loose fatty stool
This indicates a problem with the liver/gallbladder, which would also be associated with the acne. Bitters and food sources of B vitamins are highly recommended.
~Dark circles under eyes
These can be hereditary, although they are often referred to as "allergy shiners" and can again be associated with weak adrenals.
~Food passing too quickly (8-10 hours after eating)
Focus on building up your flora with fermented foods like kefir or cultured vegetables. You will also need to feed these bacteria with fibers. I highly recommend rice bran or oat bran, which are also high in B vitamins.
What I have done:
6 Liver Flushes
These don't really work:
http://curezone.com/forums/fm.asp?i=1534176#i
If you really want to cleanse the liver I suggest using bitters and food sources of B vitamins.
1 Candida Cleanse
2 Colon Cleanses
Gluten Free
Soy Free
Corn Free
Sugar Free
(Above avoidances have been continued for at least 3 months each and/or together)
(Minor Things; ACV, Coconut Oil, Multivitamin, ect.)
My recommendations are to focus on the adrenals, bitters, kefir or cultured vegetables. and fibers to start with. Also check your basal body temperature to determine your thyroid function.
~Hives on skin when scratched
hives are related to intestine and liver toxicity.
Actually this is called geographic dermatitis and it has nothing to do with the intestines or liver toxicity. This is a histamine reaction in the skin, which is caused by low adrenal function. Healthy adrenals release sufficient levels of epinephrine to counter histamine.
Weak adrenals can also contribute to hypothyroidism.
~Dry Hair
~Dry Skin
yes related to hypothyroid as hver said, but there are many routes to correct this. some basic things would be increase efa's like cold pressed flax oil,
Flax is a goitrogen. In other words it suppresses the thyroid.
acne is also an intestinal/liver toxicity issue.
Kind of. It is actually caused from high androgen levels, which include testosterone and progesterone. The liver breaks down excess hormones including the androgens, and the metabolites are then further broken down by the intestinal flora. This is why I recommend bitters to cleanse the liver, B vitamins to help the liver metabolize the hormones and zinc to help control androgen levels. "Liver flushing" does not really cleanse the liver. I have posted explanations of this numerous times.
~Stomach/Intestinal general area pain
where exactly is the pain. under right ribcage would indicate gall bladder issue.
Gallbladder issues can cause pain in a number of areas including under the sternum, clavicle or scalpula. This is why people so often confuse gallbladder attacks for heart attacks. The big give a way is that gallbladder attacks will occur roughly 30 minutes after a fatty meal and generally subside in a few hours.
~Loose fatty stool
fat is not being digested... gall bladder problems.
Fat malabsorption is a possibility, or liver problems such as steatorrhea from hepatitis. The only way the gallbladder would cause this is if it is removed. This causes the bile to dump in to the intestines where it chemically burns the intestinal walls.
~Dark circles under eyes
kidney, liver, and or intestinal toxicity.
Actually this is hereditary in some people. Otherwise it has to do with adrenal dysfunction, not liver or intestines. To get more specific on what is happening it is dilation of the capillaries allowing blood to seep in to the tissues that leads to the swelling and dark color.
Oh, I almost forgot, I'm underweight and with the whole cannot put any on, hypothyroid doesn't seem likely.
Hypothyroidism does not always cause weight gain. And again a person can have more than one issue going on. If you have something causing hypothyroidism and something else causing weight loss then you can definitely be hypothyroid and still be under weight.