Adverse reactions induced by alcoholic drinks are common. Many normal individuals will experience nasal congestion and mild flushing of the skin within minutes of ingesting alcohol. Patients who suffer from Rosacea and Seborrheic dermatitis are more prone to facial flushing from alcohol. This is not an allergy, but related purely to the vasodilator (dilated blood vessels) effects of alcohol.
- The commonest abnormal reaction to alcohol is seen in persons from an oriental background, who get flushing, increased heart rate, and symptoms of reduced blood pressure due to a genetic impairment in the metabolism of alcohol. This is sometimes referred to as 'oriental flushing syndrome'. The response is thought to be due to increased levels of acetaldehyde (in the blood, which causes signs of histamine release) due to impaired breakdown of alcohol caused by Aldehyde dehydrogenase (ALDH) deficiency. Approximately 50% of Chinese, Japanese, and Koreans are deficient in ALDH, and this has been reported to be protective against the development of alcoholism.
- Certain drugs like Metronidazole (antibiotic) and Griseofulvin (antifungal) can inhibit the effect of ALDH and cause the oriental flushing syndrome.
- The vasodilatory effect of alcohol in the stomach can increase the absorption of food allergens in the stomach and could aggravate food allergies.
- Alcohol causes the release of histamine and some wines have a high concentration of histamines
- Alcohol is a very common trigger for vasomotor rhinitis.
Reactions to various components of alcoholic beverages
If the reaction only occurs after the intake of certain alcoholic beverages, it is most likely that food additives or food allergens but not ethanol is responsible for the symptoms, eg:
Sulphites (E220 – E227) – Wine and beers cannot be made without the natural formation of sulphites. Further sulphites are also deliberately added to inhibit the growth of undesirable yeast species and to prevent secondary fermentation.
Sulphites are found naturally in grapes, as nature's way of preventing microbial growth. Wine makers have been adding sulphites to wine since the days of the ancient Greeks and Romans. They allow the wine to last longer and let it age and develop the complex flavours. Usually a no-sulphite-added wine could only last 18 months. Therefore might be suitable for sauvignon blanc and some chardonnays.
How free is sulphite-free?
The ATF, the governing body for wineries, allows wineries to call a wine sulfite-free when the levels of sulfite are under 10 parts per million (ppm).
Do white or red wine have more sulphites?
Red wines have less sulphite. Higher levels of sulphur dioxide are allowed in dry white wine and sweet white wines to prevent further fermentation of the higher levels of residual sugar.
Alcohol drinks: Important triggers for asthma
by H Valey and PJ Thomson, Nedlands, Western Australia
Reference: Clin Immunol 2000;105:462-7.
A questionnaire was used to assess the characteristics of alcoholic drink-induced asthma in 366 adult patient recruited from the Asthma Foundation from Western Australia.
The study concluded: "Alcoholic drinks, and particularly wines appear to be important triggers for asthma responses. Sensitivity to the sulfite additives in wine seems likely to play an important role in many of these reactions. Sensitivity of individuals to salicylates present in wines may also play a role".
Role of sulfite additive in wine-induced asthma: single dose and cumulative dose study
by H Valley & PJ Thompson, Perth, Western Australia
Reference: Thorax 2001 Oct; 56 (10):763-9
This study concluded that: "Only a small number of wine sensitive asthmatic patients responded to a single dose challenge with sulfited wine under laboratory conditions. This may suggest that the role of sulphites and / or wine in triggering asthmatic responses has been overestimated. Alternatively, co-factors or other components in wine may play an important role in wine-induced asthma. Cumulative sulphite dose challenges did not detect an increased sensitivity to sulphite in wine sensitive asthmatics, and an alternative approach to identifying sulfite/wine sensitive asthma may be required."
The first report was in 1980 by Von Ketel, who described 2 patients with acute reactions after drinking beer. The basic ingredients in beer causing allergies include:
- Malted Barley – made by soaking and germinating the malt grains (sometimes other cereal (wheat) could be added). Results of skin prick test and oral challenge to barley confirm an IgE-mediated allergy to Barley. Researchers in Madrid, Spain studied 3 patients who suffered anaphylactic reaction after drinking beer. The symptoms ranged from tingling sensation in the face, swelling of the lip or tongue, chest tightness, coughing, fainting and generalised hives. The 3 patients had a positive skin prick test to an extract from barley-made beer, while 20 controls had negative tests. All three were previously allergic to pollens
- Hops add the bitter flavour. Hops (Humulus lupulus) belongs to the Cannabacea family- the same family as cannabis sativa (hemp).
Pradalier A, at al, Centre d'Allergie de l'Ouest Parisien, in France report on a patient who presented 4 times with systemic urticaria, arthralgias and fever treated successfully with corticosteroids. Wild hop (Humulus lupulus) was finally proved to be the causal factor. H.L. belongs to the cannabinaceas family. Hop dermatitis in hop workers population is the most widely described clinical manifestation. Rhinitis, conjunctivitis, asthma are rare as well as contact urticaria. IgE-anti Hop induced allergies are described in the literature. However, in some cases of reactions to hop the mechanisms are uncertain: toxicity--possible role of lupuline--or immunoallergic processes with immunocomplexes (IC) (with increased IC in serum) and systemic urticaria such as in our observation
- Yeast – essential for fermentation
All alcoholic drinks depend on yeast to produce the alcohol – they are all risks, but 'real' ales contain far more than distilled spirits. Strains of yeast for distillery, baking and wine fermentation are classified as Saccharomyces cerevisiae but are not interchangeable. No allergenic difference has been observed between Baker's yeast and Brewer's yeast. Contrary to popular belief, yeast in alcoholic beverages causing allergy is very rare.
Intolerance to Histamine
Alcoholic beverages with a high histamine (some red wines) or alcohol ingested with histamine-rich foods may result in adverse reactions in persons with an impaired diamine oxidase (the enzyme that breaks down histamine) function.
The red wine provocation test: intolerance to histamine as a model for food intolerance
by F Wantke et al Vienna, Austraia
Reference: Hautartzt 1993 Aug; 44(8): 512-6
Sneezing, flushing, headache, diarrhoea, skin itch, and shortness of breath are symptoms occurring in patients intolerant to histamine after drinking 1 glass of red wine.
The role of histamine in wine intolerance was evaluated by a red wine provocation test in 28 patients with a history of wine intolerance and in 10 controls.
22 /28 patients had symptoms showing significantly higher plasma histamine levels 30 minutes after wine challenge compared with asymptomatic controls. Basal histamine levels of patients were higher than controls. Slight asthmatic attack was seen in 2/22 patients.
Terfenadine premedication significantly eliminated symptoms in 10/12 patients in a subsequent wine test.
Histamine assessment was done in 52 wines (red, white, and champagne) and in 17 beers by radioimmunoassay. Histamine levels ranged from:
- 3-120 microgrammes/l in white wine
- 15-670 micog/l in champagnes
- 60-3800 microg /l in red wines and
- 21-305 microg/l in beers
Patients intolerant to wine seem to have diminished histamine degradation probably based on a deficiency of diamine oxidase.
Salicylate is a natural chemical found in fruits, vegetables, herbs, spices and seeds.
High levels of salicylates are found in grapes, yeast, wines, and beers. (Gin, vodka and whisky have low levels of salicylates). Salicylates are common triggers for urticaria and eczema. It stands to reason that salicylates in alcoholic beverages can exacerbate or trigger urticaria and eczema.
Ethanol as a cause of hypersensitivity reactions to alcohol
If hypersensitivity reactions are experienced after the ingestion of small amounts of any type of alcohol, an allergic reaction to ethanol is likely.
Pure ethanol allergy is very rarely documented and the mechanism is not yet fully understood. A study from Germany, published in Clinical Experimental Allergy August 2002, suggest that:
- Ethanol itself is a common causative factor in hypersensitivity reactions to alcoholic beverages
- These reactions occur in a dose-dependent fashion
- A non-IgE-mediated mechanism is likely (skin prick test are negative in all cases)
- Oral provocation remain indispensable in making the diagnosis of alcohol hypersensitivity
Alcohol-induced elevations of serum IgE levels in human subjects
by A Gonzales-Quintela et al, Santiago de Compostela, Spain
Reference: Am J Emerg Med 2001 Oct; 19 (6):501-3
Several studies consistently show that total serum IgE concentrations are increased in alcoholics when compared to controls. Total serum IgE decrease after ethanol abstinence.
The association of alcohol intake with total IgE concentrations in humans is discussed in the present review.