What is the interaction between azithromycin (Zithromax (azithromycin)) and a combination of promethazine and dextromethorphan?

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From the Research

Z-pack (azithromycin) and promethazine with dextromethorphan should not be taken together without medical supervision due to potential interactions. These medications serve different purposes: Z-pack is an antibiotic that treats bacterial infections like bronchitis, pneumonia, or sinusitis, while promethazine with dextromethorphan is a combination medication used to treat cough and cold symptoms. The combination may increase side effects like drowsiness, dizziness, and confusion, particularly in older adults. Additionally, azithromycin can potentially prolong the QT interval in the heart, and promethazine may add to this risk in some patients 1.

Key Considerations

  • Azithromycin is effective in treating community-acquired pneumonia, including cases with macrolide-resistant Streptococcus pneumoniae 2.
  • The use of azithromycin in combination with other medications, such as β-lactam antibiotics, may have additional benefits in certain cases of severe community-acquired pneumonia 3.
  • However, the combination of azithromycin with promethazine and dextromethorphan is not recommended without medical supervision due to the potential for increased side effects and interactions.
  • A recent study found that azithromycin combination therapy did not significantly reduce mortality in patients with severe community-acquired pneumonia-associated acute respiratory distress syndrome 4.

Recommendations

  • If prescribed both Z-pack and promethazine with dextromethorphan, take them exactly as directed by your healthcare provider, maintaining the prescribed timing between doses.
  • Always inform your doctor about all medications you're taking to avoid harmful interactions.
  • If you experience unusual side effects like severe drowsiness, confusion, irregular heartbeat, or difficulty breathing while taking these medications together, seek medical attention immediately.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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