Rather low dose, in large parts excreted unmetabolized. No data pointing to CYP-interaction. Three references consider it safe. Occasional clinical observations of tolerance.

Adrenergic bronchodilator for systemic treatment (tabl. 2 - 4 mg, oral solution 0,4 mg/mL) of asthma, bronchitis and emphysema. Metabolized in the liver. About 35 % excreted in urine in unchanged form. Weak inhibitor of CYP 3A4. EPI-list: safe South African list: use French list: autorized Kauppinen and Mustajoki. Prognosis of acute porphyria... Medicine 1992; 71: 1-13: Reported to be tolerated (n=2) Used in porphyria ward (Sweden).

Uneventful use reported in 1 patient with acute porphyria.