|
|
Asthma
The
three papers which follow furnish strong evidence that phenytoin is useful
in asthma. Consistent
with these findings are basic mechanism studies which show PHT's ability
to relax bronchial smooth muscle, to regulate the autonomic nervous system,
and to prevent the effects of hypoxia.
Shulman,
New England Journal of Medicine (1942),341
selected seven cases of severe bronchial asthma, which were considered
intractable because they had not responded to conventional treatment.
These cases were treated with PHT. In a detailed study the author reported
marked relief of asthma in six of seven cases and partial relief in the
seventh. In
this study PHT was used exclusively and was not begun until all other
medications were eliminated. With the application of PHT six of the patients
were consistently free of attacks of bronchial asthma and the seventh
showed some improvement. Two of the patients had stubborn eczema which
cleared to a remarkable degree with PHT. The
author notes that the efficacy of PHT was further evidenced by the fact
that the patients were able to successfully engage in situations and environments
which formerly precipitated attacks of bronchial asthma.
341.
Shulman, M. H., The use of Dilantin sodium in bronchial asthma: a preliminary
report, New Eng. J. Med., 226: 260-264, 1942.
Sayer
and Polvan, Lancet (1968),401 described
sixteen patients with bronchial asthma, with frequent asthmatic crises.
Fourteen had abnormal EEGs and two had EEGs within normal limits. All
patients were taken off other medications and given PHT for an average
of forty-five days. Ten patients were closely followed up during this
period. Seven had neither asthmatic crises nor wheezing. One patient had
occasional wheezing and in the other two cases the frequency of crises
was greatly diminished.
401.
Sayar, B. and Polvan, O., Epilepsy and bronchial asthma, Lancet,
1: 1038, 1968.
Shah,
Vora, Karkhanis and Talwalkar, Indian Journal of Chest Diseases
(1970),1535 conducted a study of
the usefulness of PHT in bronchial asthma in twenty-seven patients. Both
clinical and laboratory observations were made. The
authors state that the prevention of the spread of electrical discharge
is one of the most important, interesting and unexploited pharmacological
properties of PHT. Noting that other paroxysmal disorders have responded
to PHT, they felt that its use in the paroxysmal spasms of asthma should
be explored.
In
the study of the twenty-seven patients, careful histories were recorded,
including the severity of asthma, graded by age at onset, frequency of
attacks during past twelve months, absenteeism from work, number of days
absent in the last month, and number of sleepless nights in the last month.
Effort tolerance tests were performed during and between attacks. Appraisal
of previous therapy during the last month was noted by the number of adrenaline
and/or aminophylline injections and oral drugs (bronchodilators and steroids).
Each patient had laboratory investigations, chest x-ray and electrocardiogram
to exclude any cardiopulmonary disease simulating bronchial asthma. Ventilation
studies, including maximum breathing capacity, were carried out initially
and repeated at weekly follow-up examinations. At the end of the treatment
period all examinations were repeated.
Before
starting patients on PHT all other medicines were discontinued. Dosage
was 100 mg PHT t.i.d. The trial was for one month. Assessment of subjective
and objective results was verified by all participating physicians. While
on PHT, twenty-five of the twenty-seven patients experienced impressive
relief. Fifteen of these patients showed improved ventilation tests. Although
some wheezing persisted in twelve patients, the distress was less evident.
As a whole, the patients were more relaxed. The
results of this study led the authors to suggest that PHT would seem to
be a useful anti-asthmatic agent. (A number of people with emphysema have
reported to the Dreyfus Medical Foundation that since taking PHT for other
reasons they had experienced improvement in their breathing. We are not
aware of published work on the use of PHT for emphysema. It would seem
an area for research. (See Anti-anoxic Effects of PHT-Basic Mechanisms
of Action.)
1535.
Shah, J. R., Vora, G., Karkhanis, A. V., and Talwalkar, C. V., The effect
of diphenylhydantoin on ventilation tests in airway obstruction, Indian
J. Chest. Dis., 12: 10-14, 1970.
Jain and Jain, Journal of Asthma (1991), 3348 evaluated the efficacy of phenytoin (PHT) for the relief of chronic asthma in 190 intractable asthmatics in an open trial in a rural desert area of northwest India. Phenytoin (100 mg po b.i.d. for adults and 50 mg po b.i.d. for children), used alone or as an adjuvant to other anti-asthma medications, significantly reduced the frequency and severity of asthma attacks, coughing, nocturnal awakenings and work absenteeism. Improved effort tolerance and subjective sense of well-being were noted. Phenytoin reduced the corticosteroid requirements of steroid-dependent patients. Not only were these results sustained over the 12-month treatment period, but also more than 60% of phenytoin-treated patients were able to discontinue PHT without recurrence of symptoms.
3348. Jain, S., Jain, K.C., Effect of phenytoin sodium in the management of poorly controlled bronchial asthma at a rural health center in Phalodi, Rajasthan, India, J. Asthma, 28(3): 201-11, 1991.
|