Lidocaine Topical and Nitrofurantoin Interaction
Drug interaction information between Lidocaine Topical and Nitrofurantoin.
Lidocaine Topical and Nitrofurantoin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Lidocaine Topical and Nitrofurantoin. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Both drugs can cause a blood problem that makes it hard for your body to get enough oxygen. Using them together increases the risk of this serious condition.
What To Do
Your doctor should monitor you closely for signs of low oxygen, like blue skin or trouble breathing. Use this combination with caution.
FDA Label Information
Drugs That May Cause Methemoglobinemia When Used with LIDODERM Patients who are administered local anesthetics are at increased risk of developing methemoglobinemia when concurrently exposed to the following drugs, which could include other local anesthetics: Examples of Drugs Associated with Methemoglobinemia : Class Examples Nitrates/Nitrites nitric oxide, nitroglycerin, nitroprusside, nitrous oxide Local anesthetics articaine, benzocaine, bupivacaine, lidocaine, mepivacaine, prilocaine, procaine, ropivacaine, tetracaine Antineoplastic agents cyclophosphamide, flutamide, hydroxyurea,...
Lidocaine Topical Also Interacts With
- Acetaminophen moderate
- Valproate moderate
- Chloroquine moderate
- Mexiletine moderate
- Nitroglycerin moderate
Nitrofurantoin Also Interacts With
- Dapsone Topical moderate
- Probenecid minor
- Methylprednisolone minor
Frequently Asked Questions
Can I take Lidocaine Topical and Nitrofurantoin together?
This is a moderate interaction. Your doctor should monitor you closely for signs of low oxygen, like blue skin or trouble breathing. Use this combination with caution.
How serious is the interaction between Lidocaine Topical and Nitrofurantoin?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Lidocaine Topical and Nitrofurantoin interact?
Both drugs can cause a blood problem that makes it hard for your body to get enough oxygen. Using them together increases the risk of this serious condition.
Understanding the Lidocaine Topical and Nitrofurantoin Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Lidocaine Topical belongs to the Topical Anesthetic class and Nitrofurantoin belongs to the Nitrofuran Antibiotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Both drugs can cause a blood problem that makes it hard for your body to get enough oxygen. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Lidocaine Topical has 10 total documented interactions on file in this dataset, and Nitrofurantoin has 4. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor should monitor you closely for signs of low oxygen, like blue skin or trouble breathing. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Lidocaine Topical or Nitrofurantoin based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.