Drug interactions
Insulin degludec + Phenylephrine
Severity: Minor
Insulin degludec 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 modestly raise blood glucose and so reduce the glucose-lowering effect of insulin. The effect is usually small with typical oral decongestant or short-term use.
What this interaction means in plain words
Insulin degludec 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.
Insulin degludec belongs to Endocrine; Phenylephrine belongs to Respiratory.
Why it happens
Sympathomimetic stimulation of adrenergic receptors increases hepatic glucose output and reduces insulin secretion, opposing insulin's action.
What to do
Monitor blood glucose more closely when systemic phenylephrine is used, and 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
Other interactions of Insulin degludec
Frequently asked questions
Can I take Insulin degludec with Phenylephrine?
MediHelp rates the interaction as minor. Insulin degludec 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 modestly raise blood glucose and so reduce the glucose-lowering effect of insulin. The effect is usually small with typical oral decongestant or short-term use.
How serious is the interaction between Insulin degludec 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 more closely when systemic phenylephrine is used, and 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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