G3.6: Antihistamines may help if there is a genetic tendency to overproduce histamine.

Genetic differences in more than 70 genes have been associated with increased itchiness, see summary at the end of this section. (G3.24) Calcium and serotonin levels may be involved in increased itch or arthritis pain signals being sent or perceived. (G3.25) Scratching an itch is considered rude and a chronic itch is often considered funny however it isn’t fun.

Some background information:

Too much or too little calcium and magnesium can affect pain, itching, and mood. The minerals are both electrically active, and provide energy for ion channels which control the transport of messenger chemicals like serotonin across cell membranes – such as nerve cell membranes which might feel like a sensation of itchiness or pain.     

Excess serotonin may be involved, (G3.26, G3.27), and scratching an itch can make the urge to scratch more intense, even worse afterwards, even though there may be a temporary feeling of relief while scratching. (G3.28) Adequate magnesium is essential for reducing pain in arthritis or at least may help reduce pain levels. (G3.27) An antihistamine may help for some types of itching related to genetic conditions. (G3.29)

Excess dopamine levels can also be a cause of an overwhelming urge to scratch – see “grooming behavior” in section 7. When to Report?. The solution there is to figure out why dopamine levels are that elevated. Elevated dopamine can be a symptom of hyperthyroidism but it can also be associated with other conditions.

  • An Itch You Just Can’t Scratch; NIH-funded study identifies proteins that may cause chronic itch. Summary points: The HTR7 gene was found most closely associated with chronic itch in an animal based study, however over 70 genes were found to be more expressed, more active in lab animals with chronic itch. The gene expression of the HTR7 gene was most active in the mice with the worst symptoms of scratching compared to the mice with the least sensitivity. The activity of the TRP1 receptor was also increased in animals with more symptoms. (G.24)
  • Transient receptor potential ankyrin 1 (TRPA1) receptor is involved in chronic arthritis: in vivo study using TRPA1-deficient mice. Summary points: The TRPA1 receptor is directly activated by calcium levels inside of the cell, and a variety of toxins or “noxious” (irritating) substances that are produced as a normal part of “oxidative stress” otherwise known as “inflammation” including, “4-hydroxy-2-nonenal, hydrogen peroxide, hypochloride, hydrogen sulphide, 15-delta prostaglandin J2 [2528].” and irritants from the environment or diet can also activate the TRPA1 receptor, *1.mustard oil (allyl isothiocyanate: AITC) [29], *2. cinnamaldehyde [30, 31], *3. allicin [32, 33] and *4. formalin [34]…”. (G3.25) Serotonin and other “Inflammatory mediators, such as bradykinin…[19, 35]” (G3.25) can make the receptors more sensitive which can lead to increased responsiveness of nerve endings – more pain (G3.25) or itch. (G3.24) *See the next section for more information about the chemicals in bold font and where they may be found in the diet or environment.

*People with overactive TRPA1 channels may be sensitive to:

  1. Mustard:  “mustard oil”
  2. Cinnamon:  “cinnamaldehyde'” (G3.43) );
  3. Onion or Garlic:allicin,” (G3.41)
  4. Formaldehyde:formalin,” chemically the two are very similar: (G3.42) and formaldehyde is found in the environmental and as a metabolite of some alternative sweeteners and other dietary sources. (G3.56) Environmental sources include which would include first and second hand smoke, poorly ventilated air or smog, especially when there is brand new flooring or other new plastic or vinyl  material in the living area, it  can release volatile chemicals including formaldehyde at levels that can make a sensitive person feel ill. Metabolites of the breakdown of the alternative sweetener aspartame and Neotame include menthol and formaldehyde. (G3.44) Older packages of fruit juice also may contain increasing amounts of formaldehyde as the product ages, more of the chemical is produced from other chemicals.

Magnesium, Opioids, and Neuropathic Pain.

This list and this section got much longer actually, and eventually led me back to a topic I’ve written about in 2011, and which is one of the underlying causes of overactive TRP channels. Fortunately it also has a simple solution, (G3.101), but – unfortunately – it is so simple a solution that it isn’t profitable – unfortunately for individual patient’s health and quality of life and unfortunately for the economic health of individuals and nations and businesses who are being overcharged by the medical industry for healthcare that isn’t always effective and sometimes causes harm.

It is so effective a solution for improving mood and pain and muscle cramp type symptoms that I’ve been sharing the information online since at least 2011 and the article I shared was research from 2009, (G3.101), – so the clock is ticking on how soon the evidence based medical research will reach the individual patient who is in pain. The racers at the starting line are the physicians and nurse practitioners and other health professionals who make recommendations for opioid medications in an attempt to block pain instead of trying to find and resolve the cause of the pain.

What is a nerve signal? “Pain” or “no pain”? or “on” and “off”?
Pain, however, should not just be blocked without trying to understand the cause. It is a message from the body desperately asking for help but it is not always a clear message. Pain in one area of the body may have to do with an issue in another area of the body. Instead of blocking the pain signals we need to listen to them more carefully and try to figure out what the pain signals mean and how to resolve the underlying cause of the pain. Something might be missing and need to be added back into the diet or something might be happening in excess either in the diet or lifestyle habits and need to be stopped or moderated.

Nerve signals are not specific to send the brain a message of “pain” that exclusively means “pain;” a nerve signal is more of an “on” or “off” and might indicate a variety of extremes: too hot or too cold, or too rough or too light (ticklish), or too hot peppery, (capsaicin, (G3.100), more on that later), or too mustard oily. The nerve signal is simply telling the brain that “something” happened – figure it out captain of the ship – and fix it – such as remembering to wear gardening gloves before handling wild mustard weeds, especially if you have diabetic hypersensitivity.

The TRP channels are the bridge between the world and the nerve signal. There are many types and they can respond to specific temperatures, so some might activate when it is very cold and some might activate when it is very hot. Some might react to the hot pepper and some might react to the mustard oil. They would all tell the same nerve – “something” extreme happened.

Mustard oil can cause an extremely itchy reaction. It is used to induce “hypersensitivity” in lab animals to study the condition in relation to diabetic hypersensitivity. This will be discussed in the next section in more detail. (G3.96) Wearing gloves may be advisable when pulling a patch of wild mustard if you tend to have sensitive skin or allergic reactions.  (p124, G3.97)

Antihistamines taken daily can be helpful if excess histidine is a problem.

Antihistamines taken as a daily precaution may be helpful for people with overly sensitive skin if the sensitivity is related to a tendency to overproduce histidine. (G3.29) If that is an issue, then taking an antihistamine medication daily may also help for some types of chronic pain as well, more will be included in the next section. Acupuncture is a traditional therapy that may help reduce the overactivity of TRPV channels and reduce the production of the inflammatory peptide Substance P and other cytokines. Acupuncture can affect both the opioid and the cannabinoid receptors – but without needing the prescription or having to experience the side effects! (G3.104)

See a healthcare provider for medical advice, diagnosis or treatment.

  • Disclaimer: Opinions are my own and the information is provided for educational purposes within the guidelines of fair use. While I am a Registered Dietitian this information is not intended to provide individual health guidance. Please see a health professional for individual health care purposes.

The Academy of Nutrition and Dietetics has a service for locating a nutrition counselor near you at the website eatright.org: (eatright.org/find-an-expert)

References: