Methylnaltrexone Warnings & Precautions

Before taking Methylnaltrexone, inform your doctor of all your medical conditions and medications. Certain conditions and patient groups require special precautions or may make Methylnaltrexone unsuitable.

Key Warnings

→Risk of addiction, abuse, and misuse even at prescribed doses
→Respiratory depression is the main cause of opioid-related death
→Store securely; keep out of reach of children
→Do not drive or operate machinery until you know how the drug affects you
→Risk of neonatal opioid withdrawal syndrome if used during pregnancy

Pregnancy and Breastfeeding

→Opioids should be avoided during pregnancy except when benefits clearly outweigh risks. Neonatal opioid withdrawal syndrome can occur after in-utero exposure. Use only under specialist supervision.

Older Adults

→Older adults are more sensitive to opioid effects including sedation, respiratory depression, and falls. Start with lower doses and titrate slowly. Monitor closely for adverse effects.

Chronic Conditions

→Patients with respiratory disorders (COPD, sleep apnoea), liver disease, or kidney disease require dose adjustment and close monitoring. Opioids are generally inappropriate for long-term non-cancer pain management.

When Not to Use

→Respiratory depression or severe asthma
→Paralytic ileus
→Concurrent MAOI use within 14 days (meperidine, tramadol)
→Known hypersensitivity to the specific opioid

Safety Note

Methylnaltrexone should only be taken as prescribed. If you have any concerns about whether Methylnaltrexone is suitable for you, consult your doctor or pharmacist.

Frequently Asked Questions

Is Methylnaltrexone safe for everyone?

Methylnaltrexone is not suitable for everyone. Risk of addiction, abuse, and misuse even at prescribed doses Always inform your doctor of all medical conditions before starting Methylnaltrexone.

What should I do if I miss a dose?

For scheduled dosing, take as soon as you remember unless it is nearly time for the next dose. For as-needed dosing, take when you experience pain. Never double up.

More About Methylnaltrexone

Dosage & Administration

Side Effects

Drug Interactions

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Medical Disclaimer: This drug reference is provided for informational purposes only and is not a substitute for professional medical advice. Always consult your physician or pharmacist before changing your medication. Information reviewed by the vHospital Editorial Team · Sources: WHO, BNF, FDA prescribing information.