Patients using leukotriene modifiers should consult their physicians before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications.

Of particular concern to individuals taking leukotriene modifiers are:

• Antibiotics. Medications that kill or slow the growth of bacteria. These drugs may decrease the effectiveness of leukotriene modifiers.
  
  
• Beta blockers. Medications that reduce the workload of the heart and lower blood pressure. They are commonly used to treat high blood pressure, angina or heart failure. These drugs may impact the effectiveness of leukotriene modifiers.
  
  
• Aspirin and aspirin-containing products. Leukotriene modifiers may increase the side effects of these medicines.
  
  
• Phenobarbital. A barbiturate, sedative and anticonvulsant used in the treatment of insomnia, epilepsy, anxiety and other conditions. Dosage adjustment or special monitoring of these drugs may be necessary for those taking leukotriene modifiers.
  
  
• Anticoagulants. Medications that inhibit the formation of blood clots. Patients taking anticoagulants in combination with leukotriene modifiers are at a greater risk to develop bleeding and may require closer monitoring by a physician.
  
  
• Grapefruit juice. Patients taking leukotriene modifiers may be advised by their physicians to avoid drinking grapefruit juice. Drinking grapefruit juice can lead to a buildup of certain medications in the body, increasing the risk of side effects.
  
  
• Alcohol. Patients should not drink alcohol while taking leukotriene modifiers because the combination can damage the liver.

Those who are taking other prescribed asthma drugs should continue to do so at the recommended doses unless their physician suggests otherwise.