Drug Interaction Report

Gentamicin Injection and Succinylcholine: Interaction Details

A pharmacist-reviewed analysis of the Gentamicin Injection and Succinylcholine interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Gentamicin Injection

Garamycin® I.V. Garasol Gentak
+

Succinylcholine

Anectine Quelicin
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
LinkedIn
Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 75 documented Gentamicin Injection interactions, 36 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
rapid
Evidence
theoretical
Severity
Major

What happens

Enhanced neuromuscular blockade

Interaction Deep Dive

The incidence of aminoglycoside-induced respiratory paralysis is increased when it is used with neuromuscular blocking agents. Treatment with anticholinesterase or calcium is helpful12.

Why it happens (mechanism)

Additive neuromuscular blocking effects

Literature reports

1 report — tap to read

a) Tobramycin, neomycin, gentamicin, kanamycin, and streptomycin have produced neuromuscular transmission failure in patients concurrently receiving tubocurarine, decamethonium, gallamine triethiodide, or succinylcholine 3. Enhanced neuromuscular blockade is probably the result of competitive postjunctional anticholinergic action at the neuroeffector site along with a deficit in presynaptic acetylcholine release. More than 100 cases of antibiotic-induced respiratory depression have been reported, including complete paralysis, either with aminoglycosides administered alone or in conjunction with skeletal muscle relaxants.

Common questions

Can I take Gentamicin Injection and Succinylcholine together?

Enhanced neuromuscular blockade Always confirm with your pharmacist or prescriber before making any change.

How serious is the Gentamicin Injection and Succinylcholine interaction?

It is rated major. Potentially serious — often needs a change or close monitoring.

How quickly could this interaction happen?

The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.

How strong is the evidence for this interaction?

The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

Questions for your pharmacist

  • Does my dose of Gentamicin Injection or Succinylcholine need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there a safer alternative to one of these medications for me?

References (3)

  1. Levanen J & Nordman R: Complete respiratory paralysis caused by a large dose of streptomycin and its treatment with calcium chloride. Ann Clin Res 1975; 7:47-49.
  2. Warner WA & Sanders E: Neuromuscular blockade associated with gentamicin therapy. JAMA 1971; 215:1153-1154. DOI
  3. AnonAnon: Evaluations of Drug Interactions, 2nd. American Pharmaceutical Association, Washington, DC, 1976.
Was this write-up helpful?
Gentamicin Injection

Keep reading about Gentamicin Injection

All Gentamicin Injection interactions (75) Gentamicin Injection drug information
Also serious with: Ataluren Vecuronium Pancuronium Mivacurium
Succinylcholine

Keep reading about Succinylcholine

All Succinylcholine interactions (19) Succinylcholine drug information
Also serious with: Amikacin Injection Amikacin Oral Inhalation Digoxin Gentamicin Ophthalmic
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Succinylcholine + Procaine Bacopa Bael Betel Nut Boxwood Calamus Clubmoss Dimethylsulfoxide (dmso) + 17 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

Check another combination

Our instant two-drug interaction checker is almost here.

Coming soon

The instant two-drug checker is on its way.

In the meantime, browse the directory below to look up any drug and see its documented interactions.

Still have questions about this combination?

Every question gets a real answer from a licensed pharmacist — free, and usually within a day.

Ask the pharmacist
This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.