Levalbuterol

Other short-acting sympathomimetic aerosol bronchodilators or epinephrine should not be used concomitantly with XOPENEX HFA. If additional adrenergic drugs are to be administered by any route, they should be used with caution to avoid deleterious cardiovascular effects. Other short-acting sympathomimetic aerosol bronchodilators and adrenergic drugs : May potentiate effect. ( 7 ) Beta-blockers : May block bronchodilatory effects of beta-agonists and produce severe bronchospasm. Patients with asthma should not normally be treated with beta-blockers. ( 7.1 ) Diuretics : May worsen electrocardiographic changes or hypokalemia associated with diuretics may worsen.

Consider monitoring potassium levels. ( 7.2 ) Digoxin : May decrease serum digoxin levels. Consider monitoring digoxin levels. ( 7.3 ) Monoamine oxidase inhibitors (MAOs) or tricyclic antidepressants : May potentiate effect of albuterol on the cardiovascular system. Consider alternative therapy in patients taking MAO inhibitors or tricyclic antidepressants. ( 7.4 )

7.1 Beta-blockers Beta-blockers: Beta-adrenergic receptor blocking agents not only block the pulmonary effect of beta-adrenergic agonists, such as XOPENEX HFA, but may produce severe bronchospasm in asthmatic patients. Therefore, patients with asthma should not normally be treated with beta-blockers. However, under certain circumstances, e.g., as prophylaxis after myocardial infarction, there may be no acceptable alternatives to the use of beta-adrenergic blocking agents in patients with asthma. In this setting, cardioselective beta-blockers should be considered, although they should be administered with caution.

7.2 Diuretics The ECG changes or hypokalemia that may result from the administration of non-potassium-sparing diuretics (such as loop and thiazide diuretics) can be acutely worsened by beta-agonists, especially when the recommended dose of the beta-agonist is exceeded. Although the clinical significance of these effects is not known, caution is advised in the coadministration of beta-agonists with non-potassium-sparing diuretics. Consider monitoring potassium levels.

7.3 Digoxin Mean decreases of 16% to 22% in serum digoxin levels were demonstrated after single-dose intravenous and oral administration of racemic albuterol, respectively, to normal volunteers who had received digoxin for 10 days. The clinical significance of these findings for patients with obstructive airway disease who are receiving XOPENEX HFA and digoxin on a chronic basis is unclear. Nevertheless, it would be prudent to carefully evaluate the serum digoxin levels in patients who are currently receiving digoxin and XOPENEX HFA.

7.4 Monoamine Oxidase Inhibitors or Tricyclic Antidepressants XOPENEX HFA should be administered with extreme caution to patients being treated with monoamine oxidase inhibitors or tricyclic antidepressants, or within 2 weeks of discontinuation of such agents, because the action of albuterol on the vascular system may be potentiated. Consider alternative therapy in patients taking MAO inhibitors or tricyclic antidepressants.

Risk Summary There are no adequate and well-controlled studies of XOPENEX HFA in pregnant women. There are clinical considerations with the use of XOPENEX HFA in pregnant women [see Clinical Considerations]. Following oral administration of levalbuterol HCl to pregnant rabbits, there was no evidence of teratogenicity at doses up to 25 mg/kg/day [approximately 750 times the maximum recommended human daily inhalation dose (MRHDID) of levalbuterol tartrate for adults on a mg/m 2 basis]; however, racemic albuterol sulfate was teratogenic in mice (cleft palate) and rabbits (cranioschisis) at doses slightly higher than the human therapeutic range ( see Data ).

The estimated background risk of major birth defects and miscarriage for the indicated population(s) are unknown. In the U.S. general population, the estimated risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk In women with poorly or moderately controlled asthma, there is an increased risk of preeclampsia in the mother and prematurity, low birth weight, and small for gestational age in the neonate. Pregnant women should be closely monitored and medication adjusted as necessary to maintain optimal control.

Labor or Delivery Because of the potential for beta-adrenergic agonists to interfere with uterine contractility, the use of XOPENEX HFA for the treatment of bronchospasm during labor should be restricted to those patients in whom the benefits clearly outweigh the risk. XOPENEX HFA has not been approved for the management of preterm labor. The benefit:risk ratio when levalbuterol tartrate is administered for tocolysis has not been established. Serious adverse reactions, including maternal pulmonary edema, have been reported during or following treatment of premature labor with beta 2 -agonists, including racemic albuterol.

Data Animal Data The oral administration of levalbuterol HCl to pregnant New Zealand White rabbits during the period of organogenesis found no evidence of teratogenicity at doses up to 25 mg/kg/day (approximately 750 times the MRHDID of levalbuterol tartrate for adults on a mg/m 2 basis). In a rat developmental study, a racemic albuterol sulfate (comprising approximately 50% levalbuterol)/HFA-134a formulation administered by inhalation did not produce any teratogenic effects at exposures approximately 160 times the MRHDID (on a mg/m 2 basis at a maternal dose of 10.5 mg/kg). However, other developmental studies with the racemic albuterol…