From the Guidelines
Morphine Sulphate and Tramadol have distinct differences in terms of potency, administration, and side effects, with Morphine being a stronger opioid agonist and Tramadol having a dual action mechanism. The key differences between Morphine Sulphate and Tramadol can be summarized as follows:
- Potency: Morphine is significantly more potent than Tramadol, with approximately 10mg of morphine being equivalent to 100mg of tramadol 1
- Mechanism of action: Morphine is a strong, full opioid agonist that binds primarily to mu-opioid receptors, while Tramadol is a weaker opioid with dual action, functioning as both a mu-opioid receptor agonist and inhibiting serotonin and norepinephrine reuptake 1
- Administration: Morphine is available in immediate and extended-release formulations, injectable solutions, and suppositories, typically dosed at 15-30mg every 4 hours for immediate release forms, while Tramadol is available in immediate and extended-release oral formulations, usually dosed at 50-100mg every 4-6 hours, not exceeding 400mg daily 1
- Side effects: Morphine causes more pronounced side effects including respiratory depression, sedation, and constipation, while Tramadol generally produces milder opioid side effects but carries unique risks of seizures and serotonin syndrome, particularly when combined with other serotonergic medications 1
- Indications: Morphine is typically reserved for moderate to severe pain, especially in acute settings or cancer pain, while Tramadol is often used for moderate pain or as a step-down analgesic when stronger opioids are being tapered 1 The choice between Morphine Sulphate and Tramadol should be based on individual patient needs, considering factors such as pain severity, medical history, and potential side effects, with Morphine being preferred for severe pain and Tramadol for moderate pain or as a step-down analgesic. According to the most recent guideline, clinicians may offer any of the opioids approved by the US Food and Drug Administration or other regulatory agencies for pain treatment, but should consider the pharmacokinetic properties, including bioavailability, route of administration, half-life, neurotoxicity, and cost of the differing drugs 1.
From the FDA Drug Label
Although its mode of action is not completely understood, from animal tests, at least two complementary mechanisms appear applicable: binding of parent and M1 metabolite to μ-opioid receptors and weak inhibition of re-uptake of norepinephrine and serotonin In contrast to morphine, tramadol has not been shown to cause histamine release Morphine sulfate tablets are an opioid agonist
The main differences between Morphine Sulphate and Tramadol are:
- Mechanism of action: Tramadol has a dual mechanism of action, involving both μ-opioid receptor binding and inhibition of norepinephrine and serotonin reuptake, whereas Morphine Sulphate is a pure opioid agonist.
- Histamine release: Tramadol does not cause histamine release, whereas Morphine Sulphate may cause histamine release.
- Pharmacokinetics: The pharmacokinetics of Tramadol and Morphine Sulphate are different, with Tramadol having a more complex pharmacokinetic profile due to its metabolism to the active metabolite M1 2.
- Side effects: The side effect profiles of Tramadol and Morphine Sulphate may differ, with Tramadol potentially causing less constipation and respiratory depression compared to Morphine Sulphate, but more nausea and dizziness 2.
From the Research
Differences between Morphine Sulphate and Tramadol
- Mechanism of Action: Morphine is a full opioid agonist, whereas Tramadol is a mixed-mechanism opioid drug that exerts its effects via binding mu receptors and blocking the reuptake of monoamines 3.
- Pain Management: Both Morphine and Tramadol are used to relieve moderate to severe pain management in patients. However, Tramadol is considered to have less serious adverse effects and dependency potential in therapeutic doses compared to Morphine 4.
- Chemistry and Synthesis: Morphine is a naturally occurring phenanthrene derivative, whereas Tramadol is a synthetic racemic mixture of (+)-tramadol and (-)-tramadol enantiomers 4, 3.
- Adverse Effects: Common adverse effects shared among all opioids, including Morphine and Tramadol, are nausea, vomiting, pruritus, addiction, respiratory depression, constipation, sphincter of Oddi spasm, and miosis 3.
- Metabolism: Morphine is primarily metabolized in the liver via glucuronidation, whereas Tramadol's metabolite M1 has μ-opioid receptor agonist activity but faces poor blood-brain barrier permeability 4, 5.
- Clinical Use: Both Morphine and Tramadol are commonly employed in the treatment of chronic pain in patients with Parkinson's disease, although other treatments such as dopaminergic agents, acetaminophen, and NSAIDs may also be used 6.
- Combination Therapy: Combination of Morphine with other drugs, such as gabapentin or pregabalin, has been evaluated for the treatment of neuropathic pain, whereas Tramadol has been combined with acetaminophen for pain management 7.