Pulmonary Function and Alcohol

1546 Communications to the Editor has also been reported in heroin addicts.’ Recently, we have encountered four cases of hashish addiction with digital clubbing. The detailed clinical and laboratory studies in these patients did not reveal any of the well-known causes of clubbing. No evidence of a familial etiology was discovered. The pathogenesis of clubbing is still controversial. However, increased blood flow to the distal parts of the extremities has been noted in most studies.’ Beside many other systemic manifestations, hashish may produce signs of autonomic dysfunction. The administration of tetrahydrocannabinol (psychoactive compound of cannabis plants) in vivo results in a decline of neural synthesis and release of acetylcholine with a concominant increase of catecholamines,4 which have vasodilatative properties on skeletal muscles. Adrenergic blockade to reverse the hypervascularity has been successful,’ We suggest that chronic use of hashish may elevate catecholaznine levels and may cause vasodilatation of peripheral arteries, followed by digital clubbing.