Asthma

Asthma attacks are usually triggered by the body's response to an allergy, but inhaling cold air can also trigger bronchospasms.

Asthma attacks are usually triggered by the body's response to an allergy, but inhaling cold air can also trigger bronchospasms.

As the airways become inflamed and filled with mucus, and the smooth muscles in the airways constrict, chest tightness may be experienced as the feeling of not being able to move air in and out of the lungs.  This feeling may in turn increase anxiety, which worsens the feeling of tightness.  These may occur after exposure to a trigger, or a specific irritant, or after exercise.

Not all people with asthma wheeze.  For some, chronic coughing, which often occurs during the night or after exercise, may be the only symptom.

Allergy may play a role in bruxism.  It is noticed that bruxism is more frequent in those experiencing periods of allergic rhinitis or asthma.

Asthma increases the risk of a collapsed lung.

"Symptoms of milk-protein allergy include cough, choking, gasping, nose colds, asthma, sneezing attacks..." [Annals of Allergy, 1951; 9]

Findings from animal and human studies confirm that DTP (diphtheria and tetanus toxoids and pertussis) and tetanus vaccinations can induce allergic responses [1, 2, 3, 4, 5] and can increase the risk of allergies, including allergic asthma.  An analysis of data from nearly 14,000 infants and children revealed that having a history of asthma is twice as great among those who were vaccinated with DTP or tetanus vaccines than among those who were not [6].

[1] Vaccine 1995;13: pp.669-73
[2] Pediatr Allergy Immunol 1997;8: pp.83-7
[3] Pediatr Allergy Immunol 1994;5: pp.118-23
[4] Adv Immunol 1996;61: pp.341-403 [review]
[5] J Allergy Clin Immunol 1974;54: pp.25-31
[6] J Manipulative Physiol Ther 2000;23: pp.81-90

Being overweight increases the risk of asthma. [Arch Intern Med 1999;159: pp.2582-8]  Obese people with asthma may improve their lung-function symptoms and overall health status by engaging in a weight-loss program.  A controlled study found that weight loss resulted in significant decreases in episodes of shortness of breath, increases in overall breathing capacity, and decreases in the need for medication to control symptoms. [BMJ 2000;320: pp.827-32]

Dietary consumption of apples and selenium intake (assessed by food frequency questionnaire) were each associated with a reduced risk of asthma in an English study of adults. [Am J Respir Crit Care Med 2001;164(10): pp.1823-28]

The number of people with asthma and the death rate from this condition have been increasing rapidly since the late 1980s.  Environmental pollution may be one of the causes of this growing epidemic.  Work exposure to flour or cotton dust, animal fur, smoke, and a wide variety of chemicals has been linked to increased risk of asthma. [Blanc PD, Eisner MD, Israel L, Yelin EH. The association between occupation and asthma in general medical practice. Chest 1999;115: pp.1259-64]

Slender, older women are more susceptible to various chronic lung problems such as bronchitis, pneumonia and asthma.

Asthma is simply a chronic inflammatory condition of the airways rather than some other part of the body, such as the joints.  People with asthma have inflamed, hyperreactive airways that produce excessive bronchial mucus.

Children with asthma have been shown to have a metabolic defect in tryptophan metabolism.  Tryptophan is converted to serotonin, a known bronchoconstricting agent in asthmatics.  Studies have shown that patients benefit from either a tryptophan-restricted diet or B6 supplementation to correct the blocked tryptophan metabolism.  Pyridoxine may also be of direct benefit to asthmatic patients, since it is a key cofactor in the synthesis of all the major neurotransmitters.

Ephedra contains ephedrine and variable quantities of pseudoephedrine.  These components are still widely prescribed and effective drugs in the treatment of asthma, particularly in chronic cases.

Ephedrine is an approved over-the-counter (OTC) treatment for bronchial tightness associated with asthma.  OTC drugs containing ephedrine can be safely used by adults in the amount of 12.5 to 25mg every four hours.  Adults should take a total of no more than 150mg every 24 hours and refer to labels for children's dosages.  Ephedra sinica continues to be a component of traditional herbal preparations for asthma, often in amounts of 1 to 2gm of the herb per day.

Glycyrrhizin, found in licorice root, shows steroid-like activity and has a long history of use as an anti-inflammatory and anti-allergic agent, actions which have now been documented.  Glycyrrhiza is an expectorant, which can be useful for relieving asthma.

Capsaicin, cayenne pepper's major active component, induces long-lasting desensitization of airway linings to various mechanical and chemical irritants.  This effect is probably due to capsaicin-induced depletion of substance P in the respiratory tract nerves.  The respiratory and gastrointestinal tracts contain neurons which have large numbers of substance P receptors.  Depletion of substance P may be desirable in asthma.

A small double-blind trial found that inhaled forskolin could decrease lung spasms in asthmatics. [Clin Pharmacol Ther 1993;43: pp.76-83]  It is unclear if oral ingestion of coleus extracts will provide similar benefits.

A controlled trial in a group of children with bronchial asthma found that 25 drops of ivy leaf extract given twice per day was effective in improving airflow into the lungs after only three days of use. [Münch Med Wschr 1998;140: pp.32-6]  However, the incidence of cough and shortness of breath symptoms did not change during the short trial period.

Standardized ivy leaf extract can be taken by itself or in water at 25 drops twice per day as a supportive treatment for children with asthma. [Giornale Italiano de Dermatologia Venereologia 1993;128; pp.619-24]  At least double this amount may be necessary to benefit adults with asthma.

One clinical trial with asthma sufferers found that tylophora leaf (150mg of the leaf by weight) chewed and swallowed daily in the early morning for six days led to moderate to complete relief of their asthma symptoms. [J Allergy 1969;43: pp.145-50]  In a follow-up trial with asthma patients, an alcoholic extract of crude tylophora leaves in 1gm of glucose had comparable effects to that of chewing the crude leaf. [Ann Allergy 1972;30: pp.407-12]

Another trial found similar success in reducing asthma symptoms using a tylophora leaf powder at 350mg per day. [J Indian Med Assoc 1978;71: pp.172-6]  However, the tylophora was not as effective as a standard asthma drug combination.  One double-blind trial failed to show any effect on asthma for tylophora. [Ind J Med Res 1979;69: pp.981-9]

Tylophora leaf at 200-400mg of the dried leaf per day or 1-2ml of tincture per day can be used to treat asthma. [Clinical Applications of Ayurvedic and Chinese Herbs. Warwick, Queensland, Australia: Phytotherapy Press, 1996: pp.134-6]

Two open-label, non-placebo, controlled human studies have shown picrorhiza to be of benefit in asthma. [Indian J Pharmacol 1975;7: pp.95-6, J Postgrad Med 1977;23: pp.118-20]  However, a follow-up double-blind study did not confirm these earlier findings. [J Postgrad Med 1983;29: pp.89-95]

A long-term trial of a vegan diet (elimination of all animal products) provided significant improvement in 92% of the 25 patients who completed the study.  Drinking water was limited to spring water (chlorinated tap water was prohibited), and coffee, tea, chocolate, sugar and salt were excluded. [Journal of Asthma 1985; 22:44, p.13]

The elimination of food additives is important in the control of asthma.  Some asthmatics react to additives such as sulfur dioxide, tartrazine (yellow dye #5), and sodium benzoate, as well as natural salicylates (aspirin-like substances found in many foods). [J Asthma 1985;76: pp.40-5, Pediatrics 1984;73: pp.631-7]  Sulfites in particular have been reported to cause asthma attacks in susceptible individuals.  A doctor or an allergist can help determine whether chemical sensitivities are present.

Fasting lowers the allergic reactions causing asthma.

Vitamin C, present in fruits, is a powerful antioxidant and anti-inflammatory agent.  Its anti-inflammatory activity may decrease the incidence of asthma symptoms.  A large preliminary study has shown that young children with asthma experience significantly less wheezing if they eat a diet high in fruits rich in vitamin C.

Dietary consumption of apples and selenium intake (assessed by food frequency questionnaire) were each associated with a reduced risk of asthma in a case-control study (607 cases and 864 controls) of adults aged 16-50 in England. [Am J Respir Crit Care Med 2001;164(10): pp.1823-8]

Red wine intake was associated with reduced asthma severity in a study of adults in England. [Am J Respir Crit Care Med 2001;164(10): pp.1823-1828]

Studies suggest that high salt intake may have an adverse effect on asthma, particularly in men.  In a small, preliminary trial, doubling salt intake for one month led to a small increase in airway reactivity (indicating a worsening of asthma) in men with asthma, as well as in non-asthmatics. [BMJ 1988;297:454]  At least four double-blind trials have provided limited evidence of clinical improvement following a period of sodium restriction.  It is difficult to compare the results of these studies because they used different amounts of sodium restriction.  However, they consistently suggest that increased dietary sodium may aggravate asthma symptoms, especially in men. [Clin Exp Allergy 2000;30: pp.615-27]

An older study showed that 80% of children with asthma had gastric acid secretions below normal levels.

Many studies have indicated that food allergies play an important role in asthma.  Negative reactions to food may be immediate or delayed.  Immediate onset sensitivities in children are usually due to egg, fish, shellfish, nuts, or peanuts.  Foods most commonly associated with delayed onset include milk, chocolate, wheat, citrus, and food colorings.  Elimination diets have been successful in treating asthma, especially for infants.

Magnesium levels are frequently low in asthmatics [J Lab Clin Med 1940;26: pp.340-4].  Current evidence suggests that high dietary magnesium intake may be associated with better lung function and reduced bronchial reactivity.  Intravenous injection of magnesium has been reported in most, but not all, double-blind trials to rapidly halt acute asthma attacks.

Magnesium supplements may reduce the bronchoconstriction in asthma by relaxing the muscle around the bronchial tubes.  Intravenous solutions containing magnesium and other nutrients have been used successfully to break acute asthma attacks.  Oral use improves breathing in asthmatics and the improvement correlates with serum magnesium levels.

In a preliminary trial, 18 adults with asthma took 300mg of magnesium per day for 30 days and experienced decreased bronchial reactivity. [Magnesium-Bulletin 1997;19: pp.4-6]  However, a double-blind trial investigated the effects of 400mg per day for three weeks and found a significant improvement in symptoms, but not in objective measures of airflow or airway reactivity. [Eur Respir J 1997;10: pp.2225-9]  The amount of magnesium used in these trials was 300-400mg per day (children take proportionately less based on their body weight).

Molybdenum may be useful in the treatment of certain cardiovascular conditions, asthma, allergies and mercury toxicity.  Because of its involvement with sulfur, it may be warranted to use in asthma that is associated with sulfite sensitivity.

People with low levels of selenium have a high risk of asthma. [Clin Sci 1989;77: pp.495-500]  Asthma involves free-radical damage [N Engl J Med 1991;325: pp.586-7 (letter)] that selenium might protect against.  In a small double-blind trial, supplementation with 100mcg of sodium selenite (a form of selenium) per day for 14 weeks resulted in clinical improvement in six of eleven patients, compared with only one of ten in the placebo group. [Allergy 1993;48: pp.30-6]  Most doctors recommend 200mcg per day for adults (and proportionately less for children) – a higher, though still safe, level.

Studies conducted at yoga institutions in India have reported impressive success in improving asthma.  For example, one study of 255 asthma patients found that yoga resulted in improvement or cure in 74% of cases.  Another study of 114 patients treated over one year by yoga found a 76% rate of improvement or cure and that asthma attacks could usually be prevented by yoga methods without resorting to drugs.

Another Indian study of 15 people with asthma claimed a 93% improvement rate over a 9-year period.  That study found improvement was linked with improved concentration, and the addition of a meditative procedure made the treatment more effective than simple postures and breathing exercises.  Yoga practice also resulted in greater reduction in anxiety scores than drug therapy.  Its authors believe that yoga practice helps patients through enabling them to gain access to their own internal experience and increased self-awareness.

A study of 46 adolescents with asthma found that yoga practice resulted in a significant increase in pulmonary function and exercise capacity and led to fewer symptoms and medications.  Patients were given daily training in yoga for 90 minutes in the morning and one hour in the evening for 40 days.  Practice included yogic cleansing procedures (kriyas), maintenance of yogic body postures (asanas), and yogic breathing practices (pranayama).

Quercetin appears to be important in the prevention of asthma attacks.  It has been shown to inhibit histamine release from mast cells and basophils when stimulated by antigens (triggers).  In addition, quercetin has both a vitamin C-sparing effect and a direct stabilizing effect on membranes, including mast cells.  It is also an antioxidant.  Other flavones also inhibit histamine release, but to a lesser degree.

Supplementation with 1gm of vitamin C per day reduces the tendency of the bronchial passages to go into spasm [Lung 1976;154: pp.17-24], an action that has been confirmed in double-blind research. [Ann Allergy 1990;65: pp.311-4]  This amount of vitamin C, while providing benefit, is not curative.  Beneficial effects of short-term vitamin C supplementation (i.e., less than three days) have been observed.  In one double-blind trial, 500mg of vitamin C per day for two days prevented attacks of exercise-induced asthma. [Ann Allergy 1982;49: pp.146-51]

Both treated and untreated asthmatic patients have been shown to have significantly lower levels of ascorbic acid in both serum and white blood cells.  Ascorbic acid has a wide variety of pharmacological effects that appear important in asthmatic treatment.

In one clinical trial, weekly 1,000mcg intramuscular injections produced definite improvement in asthmatic children.  Of 20 patients, 18 showed less shortness of breath on exertion, as well as improved appetite, sleep, and general condition.  When given sublingually prior to a sulfite challenge, vitamin B12 appears to be especially effective in cases of asthma caused by sulfite sensitivity.

Vitamin E has multiple actions that makes it a useful supportive agent in asthma treatment.

Vitamin B6 deficiency is common in asthmatics. [Ann Allergy 1975;35: pp.153-8]  This deficiency may relate to the asthma itself or to certain asthma drugs (such as theophylline and aminophylline) that deplete vitamin B6. [Ann Allergy 1990;65: pp.59-62]  In a double-blind trial, 200mg per day of vitamin B6 for two months reduced the severity of asthma in children and reduced the amount of asthma medication they needed. [Ann Allergy 1975;35: pp.93-7]  In another trial, asthmatic adults experienced a dramatic decrease in the frequency and severity of asthma attacks while taking 50mg of vitamin B6 twice per day. [Am J Clin Nutr 1985;41: pp.684-8]  Nonetheless, the research remains somewhat inconsistent, and one double-blind trial found that high amounts of B6 supplements did not help asthmatics who required the use of steroid drugs. [Ann Allergy 1993;70: pp.141-52]