Drug interactions
Codeine + Lorcaserin
Severity: Moderate
Codeine and Lorcaserin: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Lorcaserin is a serotonergic agent and a CYP2D6 inhibitor. It may reduce conversion of codeine to morphine and weaken analgesia, and serotonergic opioid combinations carry a theoretical risk of serotonin syndrome.
What this interaction means in plain words
Codeine and Lorcaserin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Lorcaserin inhibits CYP2D6, reducing codeine activation, and has additive serotonergic activity with opioids.
What to do
Monitor analgesic response and watch for signs of serotonin toxicity such as agitation, tremor, hyperreflexia and hyperthermia. Choose a non-CYP2D6-dependent analgesic if pain control is poor.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Codeine
- Alvimopan + Codeine Contraindicated
- Codeine + Isocarboxazid Contraindicated
- Codeine + Olanzapine / samidorphan Contraindicated
- Codeine + Phenelzine Contraindicated
- Codeine + Tranylcypromine Contraindicated
- Alfentanil + Codeine Major
Frequently asked questions
Can I take Codeine with Lorcaserin?
MediHelp rates the interaction as moderate. Codeine and Lorcaserin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Lorcaserin is a serotonergic agent and a CYP2D6 inhibitor. It may reduce conversion of codeine to morphine and weaken analgesia, and serotonergic opioid combinations carry a theoretical risk of serotonin syndrome.
How serious is the interaction between Codeine and Lorcaserin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor analgesic response and watch for signs of serotonin toxicity such as agitation, tremor, hyperreflexia and hyperthermia. Choose a non-CYP2D6-dependent analgesic if pain control is poor.
What other medicines interact with Codeine?
MediHelp also lists interactions of Codeine with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Codeine page.
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