Are antacids like Pepcid & Zantac the best solution available for Asian glow?
In recent years there has been a widespread misusage of antihistamine medications such as Zantac, Zyrtec and Pepcid AC to alleviate symptoms of Asian Flush. This article examines the evidence supporting this method and discusses the long-term health implications involved.
Antihistamine medications commonly used "off-label" to treat Asian flush symptoms
Of the many antihistamines on market, the three most commonly used varieties for alcohol flush reaction are discussed below:
- Famotidine - Commonly sold under the trade name Pepcid, Pepcid AC or Pepcid Complete. Famotidine is a histamine H2 receptor antagonist that inhibits stomach acid production. It is often used for the treatment of peptic ulcer disease and gastroesophageal reflux disease.
- Ranitidine - Found by the trade name Zantac. Ranitidine is also a histamine H2 receptor antagonist that inhibits stomach acid production. It is used in the treatment of peptic ulcer disease, gastroesophageal reflux disease, and Zollinger–Ellison syndrome.
- Cetirizine - Sold under the trade name Zyrtec. Cetirizine is a second-generation antihistamine used in the treatment of hay fever, allergies, angioedema and urticaria. It is a major metabolite of hydroxyzine, and a racemic selective H1 receptor antagonist.
Evidence supporting the efficacy of Pepcid and Zantac in attenuating a flush reaction from alcohol
Discussed below are clinical trials linking the action of antihistamines to one or more symptoms of alcohol flush reaction.
Erythema (skin flushing)
A 1988 study headed by N.S Miller, author of “The Pharmacology of Alcohol and Drugs of Abuse and Addiction”, examined the role of histamine in the expression of alcohol sensitivity in oriental subjects.
One-half of the test subjects in the study were given 50 mg of a H1 receptor antagonist similar to Zyrtec and 300 mg of a H2 receptor antagonist similar to Pepcid AC and Zantac. The second half were the placebo group.
The clearest difference between the antihistamine group and placebo group was in their degree of erythema. The antihistamine group showed a significant reduction in skin redness and also showed lower levels of systolic hypotension from the administration of alcohol.
A subsequent 2004 study aimed to look at why Japanese asthmatics experience exacerbation of asthma after alcohol consumption. They found that the alcohol by-product acetaldehyde increased airway muscle tone and made it harder for subjects to breath. This was associated with an increase in the release of histamine. A H1 receptor antagonist similar to Zyrtec was able to reverse this effect.
Safety implications of combining Antacids with alcohol
Generally speaking, combining Pepcid AC, Zantac or Zyrtec with alcohol is not safe for people with alcohol flush reaction. The is because these methods mask symptoms of acetaldehyde exposure without solid evidence of a significant reduction in blood acetaldehyde. This allows ALDH2 deficient individuals to consume more alcohol and increases their risk of acetaldehyde toxicity.
Daryl Davies, current director of the Alcohol and Brain Research Laboratory at the University of South Carolina, stressed in a recent article that alcohol flush reaction is the body telling the drinker to slow down and commence hydration.
“Using histamine-2 blockers to reduce the ‘Asian flush’ can escalate alcohol intake and increase the risk of stomach cancers, esophageal cancer and a type of skin cancer called squamous cell carcinoma … the use of H2 blockers may allow someone suffering from Asian glow to drink higher levels of alcohol, but this person shouldn’t do that. It’s just not smart.”
Professor Davies is alluding to a series of warnings issued by the National Institutes of Health (NIH) for people with alcohol flush reaction. In a media release, publicising research from scientists at the National Institute on Alcohol Abuse and Alcoholism (NIAAA) and Japan's Kurihama Alcohol Center, they stated that:
“…individuals with one copy of the inactive variant (i.e. Asian flush) are about 6-10 times more likely to develop esophageal cancer than are individuals with the fully active ALDH2 enzyme who drink comparable amounts of alcohol. Notably, these studies showed that individuals with the inactive variant who drink the equivalent of 33 or more U.S. standard drinks per week have a 89-fold increased risk of esophageal cancer compared to non-drinkers.”
In response, the International Agency for Research on Cancer mirrored these sentiments by classifying acetaldehyde from alcohol as a group 1 carcinogen:
“The agent (mixture) is carcinogenic to humans. The exposure circumstance entails exposures that are carcinogenic to humans.”
Possible alternative to Pepcid AC, Zantac and Zyrtec for the attenuation of Asian flush symptoms
A potential alternative to antacids and other antihistamine medications is an amino acid called N-acetyl cysteine or "NAC". Unlike Pepcid & Zantac, NAC does not act to reduce alcohol flush reaction by controlling histamine release, but rather blood acetaldehyde levels.
A 1995 study aimed to examine the role of N-acetyl cysteine in attenuating alcohol-related hypertension in rats. The scientists found that N-acetyl cysteine, an analogue of the dietary amino acid cysteine, binds acetaldehyde and works to prevent its damaging effect on physiological proteins.
In conclusion, the scientists stated that:
“Increase in blood acetaldehyde with ethanol treatment was significantly attenuated with N-acetyl cysteine treatment.”
One basis of merit for this alternative over the antihistamine method is that it addresses the problem of acetaldehyde exposure before histamines are released rather than simply masking the symptoms of histamine exposure.
Final word on the use of OTC antihistamines for Asian flush
The effect of Pepcid, Zyrtec & Zantac on Asian flush was discussed in light of evidence linking "off label" antihistamine use to symptomatic relief.
A small number of clinical trials have shown that antihistamines similar to Pepcid AC and Zyrtec may alleviate symptoms such as erythema (skin redness) and restricted breathing.
Despite this, it seems clear that the overarching health concerns of using antacids and other antihistamines with alcohol outweigh the slight improvements seen in symptoms.
Further research is required to identify whether antihistamine medications work to decrease blood acetaldehyde levels, or whether they only offer symptomatic relief that can mask serious long-term health threats.
Miller NS1, Goodwin DW, Jones FC, Gabrielli WF, Pardo MP, Anand MM, Hall TB (1988). "Antihistamine Blockade of Alcohol-Induced Flushing in Orientals". J Stud Alcohol. 1988 Jan;49(1):16-20.
Kawano T1, Matsuse H, Kondo Y, Machida I, Saeki S, Tomari S, Mitsuta K, Obase Y, Fukushima C, Shimoda T, Kohno S (2004). "Acetaldehyde Induces Histamine Release From Human Airway Mast Cells to Cause Bronchoconstriction". Int Arch Allergy Immunol. 2004 Jul;134(3):233-9. Epub 2004 Jun 1.
Brooks PJ, Enoch M-A, Goldman D, Li T-K, and Yokoyama A. (2009). "The Alcohol Flushing Response: An Unrecognized Risk Factor for Esophageal Cancer from Alcohol Consumption". PLoS Medicine. Vol. 6 No. 3: e1000050.
World Health Organization International Agency For Research On Cancer Lyon, France (2009). "IARC Strengthens Its Findings On Several Carcinogenic Personal Habits and Household Exposures". Press Release. No. 196.
Vasdev S1, Mian T, Longerich L, Prabhakaran V, Parai S (1995). "N-Acetyl Cysteine Attenuates Ethanol-Induced Hypertension in Rats". Artery. 1995;21(6):312-6.