Drug interactions
Diphenhydramine + Pentazocine
Severity: Moderate
Diphenhydramine and Pentazocine: 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
Diphenhydramine is a first-generation sedating antihistamine. With pentazocine, drowsiness, confusion and psychomotor impairment may be increased, particularly in older adults.
What this interaction means in plain words
Diphenhydramine and Pentazocine 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.
Diphenhydramine belongs to Respiratory; Pentazocine belongs to Musculoskeletal.
Why it happens
Additive central nervous system depression.
What to do
Monitor sedation and consider a non-sedating antihistamine, particularly in older patients. Counsel patients to avoid driving and alcohol.
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 Pentazocine
- Calcium / magnesium / potassium / sodium oxybates + Pentazocine Contraindicated
- Olanzapine / samidorphan + Pentazocine Contraindicated
- Pentazocine + Phenelzine Contraindicated
- Pentazocine + Tranylcypromine Contraindicated
- Alfentanil + Pentazocine Major
- Alprazolam + Pentazocine Major
Other interactions of Diphenhydramine
Frequently asked questions
Can I take Diphenhydramine with Pentazocine?
MediHelp rates the interaction as moderate. Diphenhydramine and Pentazocine 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. Diphenhydramine is a first-generation sedating antihistamine. With pentazocine, drowsiness, confusion and psychomotor impairment may be increased, particularly in older adults.
How serious is the interaction between Diphenhydramine and Pentazocine?
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 sedation and consider a non-sedating antihistamine, particularly in older patients. Counsel patients to avoid driving and alcohol.
What other medicines interact with Pentazocine?
MediHelp also lists interactions of Pentazocine with, for example, Calcium / magnesium / potassium / sodium oxybates, Olanzapine / samidorphan, Phenelzine. The full list is on the Pentazocine page.
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