As with all previously reported patients with pleu-ropulmonary involvement during bromocriptine treatment, all our patients were men. The appearance of pleuropulmonary changes has generally been attributed to long-term and high-dose use of the drug. In one patient, the abnormalities appeared after only two months of treatment at the maximal dose of 62 mg/ day. In our patients, the period between starting bromocriptine and detecting pleuropulmonary lesions varied from 12 months to four years, but all patients had experienced prolonged symptoms before the pulmonary disease was recognized. In contrast to most previous reports, all patients had taken only a moderate dose, the highest being 40 mg/day. birth control pills Ortho Tri Cyclen
The use of bromocriptine in the treatment of Parkinsons disease is increasing. Our findings support the suggestion that pleuropulmonary changes may be induced by this drug, and they suggest that changes may be more frequent than assumed. We are, however, unable to estimate the true incidence of such abnormalities. Our hospital deals with patients with pulmonary diseases from a population of about 350,000 people in the southern part of Finland. About 30 patients with exudative pleuritis are treated annually with an identified etiology in 80 to 90 percent. The pleuropulmonary abnormalities may appear after a relatively short period of treatment, and there may be a considerable delay in the diagnosis because the symptoms may be attributed to progression of the disease.
Although a cause-and-effect relationship has not been confirmed, the laboratory results and reversible roentgenographic abnormalities are highly suggestive of this. It was noteworthy in patient 4 that the chest roentgenogram after five months’ bromocriptine treatment was normal, but the changes were marked after 20 months treatment. He had been receiving the highest dose of the series. Although some pleural and pulmonary changes were present in patients 2 and 3 before bromocriptine treatment, such abnormalities are relatively common in older age groups. Any cause other than bromocriptine therapy for marked progression of the pleuropulmonary changes was discovered during thorough investigations. The lack of improvement in lung function may be explained by the delay in performing pulmonary function tests except in patient 2 (whose roentgenographic abnormalities during the follow-up showed only slight regression). Restriction of lung volumes with a normal or raised Kc0 was common to all patients and similar to previously reported findings in one patient.
As previously suggested, the similarity of the structure of bromocriptine and methysergide, a drug with known pleuropulmonary side effects, might explain a similar action of bromocriptine at serotoninergic synapses. The clinical features and studies of pleural fluid in four patients with methysergide-induced pleuropulmonary disease are similar to our findings.
Follow-up studies of pulmonary function in patients after starting bromocriptine treatment should give more exact information on the suggested cause-and-effect relationship and incidence of the condition; they may also allow the detection of subclinical cases. Measurements of ESR, C-reactive protein, and sequential chest roentgenograms are recommended at regular intervals in patients receiving prolonged treatment with bromocriptine.