Theophylline, has in the past been a mainstay in the treatment of moderate to severe asthma, but is less popular than it used to be. Recently, however, there has been a renewed enthusiasm for the use of theophylline in the treatment of asthma, because of newly identified anti-inflammatory and immunomodulatory effects. Several studies have demonstrated that theophylline inhibits histamine release and suppresses inflammatory cell activation. Recent studies have also found evidence of theophylline’s effects in modulating T-cell counts in peripheral blood and biopsy specimens, reducing activated eosinophils in biopsy specimens, and attenuating allergen-induced histamine release from mast cells.
Theophylline is particularly effective in controlling the late-phase allergic reaction of atopic asthma. The late-phase reaction is thought to be the most important reaction involved in the development of airway hyperreactivity, and hyperreactive airways are prone to go into spasm at any insult, from cold air to strong perfume.
At therapeutic blood levels, theophylline reduces bronchoconstriction and associated airway hyperresponsiveness, inhibits both immediate and late bronchoconstriction following antigen challenge, and diminishes the influx of neutrophils. These anti-inflammatory and mucociliary effects—together with the drug’s ability to improve diaphragmatic muscle functions—may also explain theophylline’s beneficial effect in chronic obstructive pulmonary disease. It may be interesting to note that theophylline also relaxes spasms of the lower airways independent of the type of mediator that induces bronchoconstriction.
Maintaining therapeutic levels of theophylline while avoiding wide swings between toxic and subclinical dosage ranges has long been a challenge. However, with the advent of controlled- and sustained-release theophylline preparations such as Theo-24, this challenge has become much simpler.
Sustained-release theophylline preparations require fewer daily doses. This not only enhances patient compliance, resulting in better asthma control, but also permits improved maintenance of therapeutic levels throughout the day and night.
Because asthma has such a strong inflammatory component, most clinicians treat asthma patients with aggressive anti-inflammatory medications in their initial regimens. However, as our understanding of asthma increases, it is important for clinicians to recognize that effective asthma regimens are often idiosyncratic, requiring drug regimens to be individualized to best meet the needs of the patient.
Theophylline is particularly effective in controlling the late-phase allergic reaction of atopic asthma. The late-phase reaction is thought to be the most important reaction involved in the development of airway hyperreactivity, and hyperreactive airways are prone to go into spasm at any insult, from cold air to strong perfume.
At therapeutic blood levels, theophylline reduces bronchoconstriction and associated airway hyperresponsiveness, inhibits both immediate and late bronchoconstriction following antigen challenge, and diminishes the influx of neutrophils. These anti-inflammatory and mucociliary effects—together with the drug’s ability to improve diaphragmatic muscle functions—may also explain theophylline’s beneficial effect in chronic obstructive pulmonary disease. It may be interesting to note that theophylline also relaxes spasms of the lower airways independent of the type of mediator that induces bronchoconstriction.
Maintaining therapeutic levels of theophylline while avoiding wide swings between toxic and subclinical dosage ranges has long been a challenge. However, with the advent of controlled- and sustained-release theophylline preparations such as Theo-24, this challenge has become much simpler.
Sustained-release theophylline preparations require fewer daily doses. This not only enhances patient compliance, resulting in better asthma control, but also permits improved maintenance of therapeutic levels throughout the day and night.
Because asthma has such a strong inflammatory component, most clinicians treat asthma patients with aggressive anti-inflammatory medications in their initial regimens. However, as our understanding of asthma increases, it is important for clinicians to recognize that effective asthma regimens are often idiosyncratic, requiring drug regimens to be individualized to best meet the needs of the patient.
source:M. Eric Gershwin M.D., Allergy and Asthma Magazine
Reference: M. Weinberger and H. Hendeles, "Theophylline in Asthma," New England Journal of Medicine, vol. 334, no. 21 (May 23, 1996).
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