Abstract
Lithium is accepted as the gold standard for long term treatment in bipolar affective disorder. However, this specific drug has various side effects, which restrict its use such as cardiologic. To our knowledge, there is only one reported case of pulmonary hypertension due to lithium therapy in the literature.
Here we are presenting a case that developed pulmonary hypertension associated with long-term lithium treatment without any prior diagnosis of a cardiac or pulmonary disease. A 43-year-old female patient had a diagnosis of bipolar disorder. Before lithium treatment, her cardiac examination and laboratory tests were normal. After a five year regular lithium 1200 mg/day lithium and 300-600 mg/day quetiapine treatment she had palpitation. It was investigated in detail; a cardiologist diagnosed her as pulmonary hypertension. Other known causes of pulmonary hypertension were investigated and eliminated both clinically and laboratory. In these conditions pulmonary hypertension was attributed to lithium treatment and we decided to change her pharmacotherapy. During exchange, she had a manic episode. Forty-five days after lithium discontinuation, PAP was detected 30-35 mmHg in the cardiac examination. Although this patient had concurrent quetiapine medication when the pulmonary pressure decreased, lithium was discontinued but quetiapine was continued in higher doses.
Current researches about lithium focus on the behavioural and neurochemical effects of this drug. Although some authors think that a new side effect should be expected for drugs like lithium, which was in use over half a century, we have to be aware of the side effects. However, any possible new side effect of lithium has to be analyzed in detail, and, before to attribute the responsibility of a new side effect to lithium, compelling evidence is required.

Key words: lithium, pulmonary hypertension, side effect