Known causes of eosinophilic pulmonary disease include Allergic bronchopulmonary aspergillosis Drug-induced pneumonitis (eg, caused by therapeutic drugs, such as antibiotics, phenytoin, or L - tryptophan) Infections (especially helminthic infections) Inhaled toxins (eg, recreational drugs, such as cocaine) Systemic disorders (eg, eosinophilic granulomatosis with polyangiitis [formerly Churg-Strauss syndrome]) Often the cause is unknown.