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Allergy: Butterbur (Petasites hybridus)
July 3, 2009 | Leave a Comment
Butterbur (Petasites hybridus)
Another interesting allergy treatment involves the herb butter-bur. This botanical medicine has been used to treat symptoms of migraine headaches, asthma, and allergy. It has anti-inflammatory activity and blocks the formation of compounds called leukotrienes (pronounced lew-co-TRY-eens). These rascals cause all sorts of mischief in the nose, including itching, sneezing, swelling, and congestion. In some respects, leukotrienes may be even more of a problem than histamine. Leukotrienes contribute to the inflammatory cascade that underlies both allergy and asthma. The prescription asthma and allergy drug Singulair (montelukast) also works by inhibiting leukotriene formation.
Swiss researchers compared butterbur with the antihistamine cetirizine (Zyrtec) in a randomized, double-blind study. They found that both products were equally effective at controlling symptoms, but butterbur was significantly less sedating than Zyrtec. 43
Q. I have suffered from chronic sinusitis, which in turn led to bronchitis and frequently into pneumonia. My physician put me on Allegra and then switched me to Clarinex.
I continued to have sinusitis and pneumonia annually for 5 years, so my doctor sent me to an allergist. He diagnosed several allergies and added a prescription for Nasacort to the Clarinex.
Two years ago, having suffered through another bout of sinusitis and pneumonia, I saw an integrative alternative medicine physician. He took me off Clarinex and prescribed butterbur, stinging nettles, and quercitin instead. I’ve taken this combination for 2 years and it has reduced the frequency of the sinusitis.
I read that I should take butterbur only 6 weeks a year. Now I am concerned about the danger of liver damage.
A. Pharmacologist David Kroll, PhD, offered this clarification on butterbur. “I wanted to follow up on a
reader who wrote to your newspaper column regarding the potential liver toxicity of butterbur (Petasites hybridus), an herb that’s become popular due to positive efficacy trials in migraine prevention and allergic rhinitis. While the herb is potentially toxic to the liver, it shouldn’t be a problem with high-quality products like Petadolex. I do-fear that some less honorable companies may latch onto this herb and not take such care with the high-tech extraction process that is necessary to reduce the risk. That might lead to some major liver injury cases.”
There is one fly in the ointment, however. Concerns have been raised about potential liver toxicity associated with compounds in butterbur. If the herbal preparation is not manufactured under very stringent quality-control conditions, there could be problems. As a result, we suggest that people use butterbur only temporarily (say, for 6 weeks during hay fever season) and that they monitor their liver enzyme activity with medical supervision. One product that should be safe is Petadolex. The German manufacturer is Weber and Weber, and it is available in the United States.
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Drugs for Allergy Treatment
July 1, 2009 | Leave a Comment
Allergy is a general term applied to certain types of hypersensitivity reactions, some of which such as hayfever are well known, but the factors that cause such reactions vary widely in their nature. In brief, an allergic reaction is immunologically mediated, and originates in an exposure to an excitatory substance referred to as an antigen, which in sensitive individuals is followed by the production of antibodies. Antigens are often protein in nature, and eggs, peanut products, wasp and bee stings, as well as drugs, can function as antigens. Subsequent re-exposure to the antigen may give rise to an antigen-antibody
reaction, which is linked with the release of cell-bound histamine and other
spasmogens, which in turn act upon various tissues to produce the allergic
response. The response may manifest itself in several ways, such as hayfever, rhinitis, bronchoconstriction and rash or urticaria. In severe allergic reactions (anaphylactic shock), an alarming fall in blood pressure may occur with respiratory distress, and requires the immediate i.m. injection of adrenaline
solution (0.5-1 ml) together with i.v. hydrocortisone 200 mg and resuscitation measures.
It should be noted that the anaphylactic reactions that occur after the first dose of certain drugs, including contrast media, are more in the nature of an idiosyncratic-toxic reaction than an immunologically mediated response, but may be no less severe, and resuscitation facilities should always be available.
In less severe allergic reactions such as hayfever and allergic rhinitis, antihistamines are widely used for symptomatic relief. They do not interrupt the chain of antigen-antibody-histamine release, but block the access of the released histamine to the sensitized tissues. Their action is palliative and not curative, and the response to treatment is often variable.
They are usually effective in hayfever, urticaria and insect bites, but are of no value in allergic asthma. Some antihistamines also have a sedative action, which may be useful in urticaria, but undesirable in other conditions. This sedative side-effect is less marked with some of the newer antihistamines (see Table 2). In overdose they may cause convulsions in young patients. The extended local
application of antihistamines should be avoided, as antihistamines may themselves cause an allergic-type dermatitis. Side-effects include dry mouth, blurred vision and occasional gastrointestinal disturbances. Patients should be warned that drowsiness is a common side-effect that may affect car-driving ability. Attempts have been made to desensitize susceptible patients by injections of specific antigens, such as grass pollens. The method is not without risk, particularly in asthmatic patients, and should be carried out only by experts.
Approved names Brand names Daily dose range
acrivastine* Semprex 24 mg
asternizole* Hismanal, Pollen-Eze 10 mg
azatadine Optimine 2-4 mg
brompheniramine Dimotane 12-32mg
cetrizine* Zirtek 10 mg
chlorpheniramine Piriton 12-24mg
clemastine Tavegil 1-2 mg
cyproheptadine Periactin 8-32 mg
loratadine* Clarityn 10 mg
mezquitazine Primalan 5-10 mg
phenindamine* Thephorin 75-150 mg
pheniramine Daneral SA 75-150mg
promethazine Phenergan 20-75 mg
terfenadine* Triludan 60-120 mg
trimeprazine Vallergan 30-100 mg
triprolidine Actidil, Pro-Actidil 7.5-15 mg
*Antihistamine with reduced sedative effects