What is the recommended adult dosage of promethazine with codeine (codeine phosphate and promethazine hydrochloride)?

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From the Guidelines

The recommended adult dose of promethazine with codeine is 5 mL (containing 6.25 mg promethazine and 10 mg codeine) taken by mouth every 4-6 hours as needed, not to exceed 30 mL in 24 hours, based on the general guidelines for cough management in patients with lung cancer 1.

Key Considerations

  • The medication should only be taken as prescribed by a healthcare provider and for the shortest duration necessary to control symptoms, usually for acute cough and upper respiratory symptoms.
  • It's essential to use the measuring device provided with the medication for accurate dosing.
  • This combination medication works because promethazine helps reduce coughing by suppressing the cough reflex in the brain, while also providing antihistamine effects, and codeine acts as both a cough suppressant and mild pain reliever.

Important Safety Information

  • Due to its codeine content, this medication carries risks of dependence, respiratory depression, and other serious side effects 1.
  • It should not be combined with alcohol or other central nervous system depressants.
  • Patients should avoid driving or operating machinery while taking it due to sedative effects.

Dosage and Administration

  • The typical dosage is 5 mL every 4-6 hours as needed, with a maximum of 30 mL in 24 hours.
  • The patient’s previous exposure to opioids will dictate the initial starting dose, as suggested in the study 1.
  • For patients with lung cancer who are experiencing nonspecific cough and who are in the palliative stage of their illness, a bedtime dose of codeine may be helpful in suppressing cough and inducing an undisturbed sleep 1.

From the Research

Dosage Information

  • The provided studies do not specify the exact dosage of promethazine with codeine that an adult can take 2, 3, 4, 5.

General Safety Precautions

  • It is known that opioids, including codeine, can cause respiratory depression, which can be fatal 2, 4, 5.
  • The combined use of opioids and other substances, such as benzodiazepines, can increase the risk of respiratory depression and other adverse events 4.

Opioid-Related Risks

  • Opioid drugs, including morphine, oxycodone, heroin, and fentanyl, can cause respiratory depression and brain hypoxia, which can be dangerous and even lethal 5.
  • The development of tolerance and the degree of respiratory depression can vary depending on the specific opioid agonist and the individual's response to it 2.

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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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