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Drug

Codeine-Guaifenesin

Pronounced

"gweye-FEN-eh-sin/KO-deen"

Drug Interactions

See also Warning section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: cimetidine, naltrexone, samidorphan.

Guaifenesin is available in both prescription and nonprescription products. Check the labels on all your medications carefully to make sure you are not taking more than one product that contains guaifenesin.

The risk of serious side effects (such as slow/shallow breathing, severe drowsiness/dizziness) may be increased if this medication is taken with other products that may also cause drowsiness or breathing problems. Tell your doctor or pharmacist if you are taking other products such as other opioid pain or cough relievers (such as morphine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

Other medications can affect the removal of guaifenesin/codeine from your body, which may affect how guaifenesin/codeine works. Examples include azole antifungals (such as ketoconazole), bupropion, fluoxetine, macrolide antibiotics (such as erythromycin), paroxetine, quinidine, rifamycins (such as rifabutin, rifampin), ritonavir, certain drugs used to treat seizures (such as carbamazepine, phenytoin), among others.

This medication may interfere with certain lab tests (such as urine 5-HIAA levels, urine VMA levels, amylase/lipase levels), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

  • Negative Interactions

    1
    • Codeine

      Teas and Herbs with Tannin

      Reduces Effectiveness

      Tannins are a group of unrelated chemicals that give plants an astringent taste. Herbs with large amounts of tannins may interfere with the absorption of codeine and should not be taken together with codeine or codeine-containing products. Herbs containing high levels of tannins include green tea (Camellia sinensis), black tea, uva ursi (Arctostaphylos uva-ursi), black walnut (Juglans nigra),red raspberry (Rubus idaeus),oak (Quercus spp.), and witch hazel (Hamamelis virginiana).

      Teas and Herbs with Tannin
      Codeine
      ×
      1. Brinker F. Interactions of pharmaceutical and botanical medicines. J Naturopathic Med 1997;7(2):14-20.
  • Supportive Interactions

    2
    • Codeine

      Fiber

      Reduce Side Effects

      This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.

      Propoxyphene may cause gastrointestinal (GI) upset. Propoxyphene-containing products may be taken with food to reduce or prevent GI upset. A common side effect of narcotic analgesics is constipation. Increasing dietary fiber (especially vegetables and whole-grain foods) and water intake can ease constipation.

      Fiber
      Codeine
      ×
      1. Threlkeld DS, ed. Central Nervous System Drugs, Narcotic Agonist Analgesics. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Feb 1990, 242-3v.
    • Codeine Phosphate

      Fiber

      Reduce Side Effects

      This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.

      Propoxyphene may cause gastrointestinal (GI) upset. Propoxyphene-containing products may be taken with food to reduce or prevent GI upset. A common side effect of narcotic analgesics is constipation. Increasing dietary fiber (especially vegetables and whole-grain foods) and water intake can ease constipation.

      Fiber
      Codeine Phosphate
      ×
      1. Threlkeld DS, ed. Central Nervous System Drugs, Narcotic Agonist Analgesics. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Feb 1990, 242-3v.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

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