Drug interactions
Insulin degludec / insulin aspart + Phenylephrine
Severity: Minor
Insulin degludec / insulin aspart and Phenylephrine: minor 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
Systemic phenylephrine may raise blood glucose modestly through adrenergic effects, partly opposing insulin action. This matters mainly with repeated or high systemic doses in diabetic patients.
What this interaction means in plain words
Insulin degludec / insulin aspart and Phenylephrine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Adrenergic stimulation increases hepatic glucose output and opposes insulin effect.
What to do
Monitor blood glucose when systemic phenylephrine is used, especially with infusions or repeated oral doses. Adjust insulin if sustained hyperglycemia occurs.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Phenylephrine
- Isocarboxazid + Phenylephrine Contraindicated
- Phenelzine + Phenylephrine Contraindicated
- Phenylephrine + Tranylcypromine Contraindicated
- Bromocriptine + Phenylephrine Major
- Cocaine + Phenylephrine Major
- Dihydroergotamine intranasal + Phenylephrine Major
Frequently asked questions
Can I take Insulin degludec / insulin aspart with Phenylephrine?
MediHelp rates the interaction as minor. Insulin degludec / insulin aspart and Phenylephrine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Systemic phenylephrine may raise blood glucose modestly through adrenergic effects, partly opposing insulin action. This matters mainly with repeated or high systemic doses in diabetic patients.
How serious is the interaction between Insulin degludec / insulin aspart and Phenylephrine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood glucose when systemic phenylephrine is used, especially with infusions or repeated oral doses. Adjust insulin if sustained hyperglycemia occurs.
What other medicines interact with Phenylephrine?
MediHelp also lists interactions of Phenylephrine with, for example, Isocarboxazid, Phenelzine, Tranylcypromine. The full list is on the Phenylephrine page.
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