Orphenadrine

For an informed discussion with your doctor or pharmacist. This information collection is not a clinically validated interaction checker. Missing data do not establish safety. Do not change or stop prescribed medicines on the basis of this information. The findings apply to the specific conditions studied; laboratory and animal studies cannot be directly extrapolated to humans.

Active substance: Orphenadrine

Examples of brand names: Norflex [DE]

ATC code: M03BC01

Main use (for orientation): Muscle spasms

Documented research summary

An MCAS pain case with marked improvement during orphenadrine + CBD oil; no comparator arm, pharmacokinetics or interaction causality. Do not present as established treatment or safety.

Uncertainties and limitations

Shared enzymes must not be equated with clinical evidence of an interaction; CBD/THC findings cannot be extrapolated to other cannabinoids.

Separately recorded findings

1 separately recorded finding. Each statement applies to its documented study context.

CBD – clinical signals

Finding ID: B0263

Type of result: Case report

Observation: Improvement in refractory MCAS pain reported following orphenadrine plus CBD oil.

Mechanism: Combined treatment, mechanism not isolated

Study type: Single case

Context studied: Improvements at follow-up after 4 and 20 weeks; abstract reports 56% lower pain severity and 87% less impairment.

Clinical interpretation: Hypothesis-generating, not a causal pair-specific drug–drug interaction

Limitations and uncertainties: No comparison or pharmacokinetics; individual substances' contributions cannot be determined; not a recommendation or evidence of safety.

Original sources for this finding: A Treatment Approach for Severe Pain in Mast Cell Activation Syndrome: A Case Report. [BMED41370840]

References and access status

[BEWEB_ORPH] Orphenadrine Hydrochloride50mg/5ml Oral Solution – SmPC

Original source / bibliographic reference

Authors: Rosemont Pharmaceuticals Limited

Year: 2023

Source type: Official UK product information/emc

Source access – 23 October 2026: Source destination was accessible when checked.

Bibliographic attribution or source identity cross-checked.

[BMED41370840] A Treatment Approach for Severe Pain in Mast Cell Activation Syndrome: A Case Report.

Original source / bibliographic reference

Authors: Russo MA, Santarelli DM.

Year: 2025

Source type: Publication; title and abstract reviewed

DOI: 10.1213/xaa.0000000000002115

PMID: 41370840

Source access – 23 October 2026: Automated direct retrieval was restricted; this does not establish that the link is broken.

Bibliographic attribution or source identity cross-checked.

PubMed – bibliographic reference / abstract

DOI – publisher access (access restrictions may apply)

Research as of 23 October 2026. Not all original full texts could be reviewed in full. Source accessibility and the strength of scientific evidence must be assessed separately. An accessible link does not establish medical approval; a bibliographic record with an abstract does not replace the original full text.

Drug search and explanation of the evidence · Guide: cannabinoids and medicines · Author and responsibility