Pseudoephedrine

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: Pseudoephedrine

Examples of brand names: Reactine duo [DE; combination product]

ATC code: R01BA02

Main use (for orientation): Rhinitis

Documented research summary

An RCVS/PRES case (27366300) following recent cocaine, marijuana and pseudoephedrine use is a signal involving multiple exposures. No isolated cannabinoid–pseudoephedrine causality or CYP-mediated drug–drug interaction demonstrated.

Uncertainties and limitations

Documented individual title/abstract review with selected relevant full texts; not an exhaustive worldwide systematic review and no independent human professional approval. Missing data do not establish safety. All 28 cannabinoids define the search scope, not 28 clinically studied pairs per active substance.

Separately recorded findings

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

Cannabis; composition not quantified – clinical signals

Finding ID: B0462

Type of result: Context-specific finding

Observation: RCVS/PRES described following recent pseudoephedrine, cocaine and marijuana use.

Mechanism: Multiple vasoactive exposures in the setting of reversible cerebral vasoconstriction syndrome.

Study type: Single case, multiple exposures

Context studied: 52-year-old man; original abstract.

Clinical interpretation: Limited clinical signal; sample size, multiple exposures or an uncontrolled design restrict causal and quantitative assessment.

Limitations and uncertainties: No isolated pseudoephedrine–cannabinoid causality or measured pharmacokinetic mechanism; cocaine and other factors prevent attribution to the pair.

Original sources for this finding: Diagnosing RCVS Without the CV: The Evolution of Reversible Cerebral Vasoconstriction Syndrome. [VF_P_27366300]

References and access status

[VF_L_D0353] Sudafed Decongestant Tablets - Summary of Product Characteristics (SmPC) - (emc) | 6199

Original source / bibliographic reference

Authors: Marketing authorisation holder; product information via emc

Year: 2025

Source type: Official medicine information; relevant identity, PK, PD and DDI sections read individually

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

Bibliographic attribution or source identity cross-checked.

[VF_P_27366300] Diagnosing RCVS Without the CV: The Evolution of Reversible Cerebral Vasoconstriction Syndrome.

Original source / bibliographic reference

Authors: Jacoby N, Kaunzner U, Dinkin M, Safdieh J.

Year: 2016

Source type: Scientific publication; precise study type and suitability described in the finding or individual review

DOI: 10.1177/1941874415599576

PMID: 27366300

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

Bibliographic attribution or source identity cross-checked.

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