Opioid Agonist

September 15, 2023

Welcome! In the previous Pharmacy Phriday, we reviewed pain management in the prehospital setting. As promised, this week, we will review the use of Morphine Sulphate within UH’s Pain Management protocol. Morphine is another narcotic option in that protocol when either Fentanyl or Dilaudid are not available. 

Morphine, a medication derived from poppy seeds, has been a mainstay in prehospital pain management since the 1970s. Like other opiates, Morphine attaches to opiate receptors, reducing the ability of nerves to transmit impulses, thus providing pain relief and sedation. 

Though the medication has been replaced by Fentanyl in many protocols across the country, it remains an option when drug shortages occur. And it remains a very effective option. When used carefully, administered in a slow, controlled manner, with constant monitoring, Morphine is very effective and safe. 

In cases of a patient experiencing chest pain or most other non-traumatic pain, Morphine can be administered at an adult dose of 2.5 mg - 5mg IV/IM, repeated at 10 minutes to a 10 mg maximum. Pediatric patients can receive Morphine for severe pain management at a dosage from 0.05 - 0.1 mg/kg IV/IM, repeated at 10 minutes to a maximum dose of 4mg. When administering the medication via the IM route, a dose at the higher end of the range is usually recommended. Dosing titrated to the effect of pain relief is also recommended.

Morphine can cause a host of symptoms related to depression of the central nervous system. Severe respiratory depression is the most feared complication of Morphine in cases of overdose. It is thus contraindicated in cases of respiratory depression. Morphine can also have a vasodilation effect in the body decreasing blood pressure and is thus not recommended for those with a head injury, hypotension, and multi-system trauma.   Patients who receive Morphine too quickly tend to have more side effects, so slow administration is preferred.

The provider must be sure to monitor the patient for any untoward effects. Monitoring should include continuous ECG monitoring, pulse oximetry, and frequent vital signs as a minimum. Capnography is strongly recommended and required when the patient has previous pain medication use or repeat doses are given by EMS. Be prepared to treat any side effects with Narcan as well as airway and other resuscitative equipment. Immediate injection of naloxone is required to reverse the effects of Morphine.

Proper documentation when using Morphine or any other medication for analgesia is critical. Key documentation elements should include documentation of the patient’s vital signs with pulse oximetry, investigating patient allergies prior to administration of the medication, documentation of the initial patient pain scale assessment, documentation of medication administration with the correct dose, and documentation of the reassessment of the patient with repeat vital signs and patient pain scale assessment.

Patients often report nausea and vomiting when receiving Morphine or other analgesics, which is why, in many cases, administration of an antiemetic such as ondansetron is also suggested. UH protocols list this as a consideration for the provider. 

Have a great day. As always, stay safe!


The UH EMS-I Team

University Hospitals