Levonorgestrel

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: Levonorgestrel

Examples of brand names: PiDaNa [DE]; Mirena [DE]

ATC code: G03AC03

Main use (for orientation): Contraception

Documented research summary

Synthetic agonists and behavioural surveys do not establish a target-cannabinoid–levonorgestrel interaction or contraceptive failure. Missing data do not establish safety.

Uncertainties and limitations

The 28 cannabinoid names in the register define the search scope, not 28 clinically studied pairs. Missing data do not establish safety.

No complete new systematic literature search and no independent medical or pharmaceutical professional approval. Note the dosage form and the country of authorisation of the product information.

Oral emergency contraception reviewed, not an intrauterine system or every combined pill.

Structured assessment

Category: Drug context

Cannabinoid scope: 28 register names within the documented search scope; no newly established direct finding for the target cannabinoid–drug pair. This must not be equated with 28 clinically studied combinations.

Evidence status: Drug properties from regulatory product information; insufficient data for a direct cannabinoid–drug pair finding in the material assessed.

Mechanism / drug context: Predominantly CYP3A4 hydroxylation and conjugation; no active metabolites reported.

Type of supporting material: Targeted product-information review and documented individual literature screening; no newly verified direct cannabinoid–drug pair study.

Clinical interpretation: The clinical relevance of a specific cannabinoid combination has not been determined. Drug context may warrant individual professional review, but neither a blanket warning level nor an assurance of safety.

Context: Oral emergency contraception reviewed, not an intrauterine system or every combined pill.

Drug context and gaps in search results are not measured interactions. The source role below describes which statement the source actually supports.

Source role [VF_L_D0436]: Medicine information: properties of the active substance

Statement supported: Predominantly CYP3A4 hydroxylation and conjugation; no active metabolites reported. Product information: drug context, not evidence for a specific cannabinoid pair or proof of safety.

Source: Levonelle 1500 microgram tablet - Summary of Product Characteristics (SmPC) - (emc) | 133 [VF_L_D0436]

Source role [VF_P_37926338]: Screened search result: no established pair evidence

Statement supported: Synthetic agonist WIN55,212-2 in a hormone combination; no evidence of a CBD/THC effect on levonorgestrel in humans.

Source: Behavioral characterization of co-exposure to cannabinoids and hormonal contraceptives in female rats. [VF_P_37926338]

Source role [VF_P_9391901]: Screened search result: no established pair evidence

Statement supported: Contraceptive behaviour/substance use in a survey; no pharmacokinetic measurement of the pair.

Source: Use of hormonal methods of birth control among sexually active adolescent girls. [VF_P_9391901]

Source role [C_PROTOCOL_D0436]: Documented search result

Statement supported: Documented title/abstract search scope for the active substance. The link displays the reproducible search query, not a study or proof that no interaction exists. Search date: 23 October 2026. Further search runs are documented in the research dataset.

Source: Reproducible literature search strategy: Levonorgestrel [C_PROTOCOL_D0436]

Scope of review: Individual research with documented title/abstract screening and targeted review of original sections. This is not exhaustive evidence that interactions are absent.

Unresolved source question: The existing individual review, label review and literature screening were read in full; targeted original PK/interaction passages were checked again, but not all product information and search results were newly reviewed in full text. Search findings are limited to the documented V5 search runs. The linked excluded search result was rechecked using its archived abstract or correction metadata record; this does not imply complete new access to the full text.

Separately recorded findings

No separately substantiated finding for this drug–cannabinoid pair is recorded within the documented scope of review. This does not prove that no such study exists anywhere or that the combination is safe.

References and access status

[VF_L_D0436] Levonelle 1500 microgram tablet - Summary of Product Characteristics (SmPC) - (emc) | 133

Original source / bibliographic reference

Authors: Marketing authorisation holder; product information via emc

Year: 2021

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_37926338] Behavioral characterization of co-exposure to cannabinoids and hormonal contraceptives in female rats.

Original source / bibliographic reference

Authors: Fattore L, Pisanu A, Concas L, Casula C, Siddi C, Pisu MG, Serra M, Concas A, Porcu P.

Year: 2024

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

DOI: 10.1016/j.pnpbp.2023.110890

PMID: 37926338

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)

[VF_P_9391901] Use of hormonal methods of birth control among sexually active adolescent girls.

Original source / bibliographic reference

Authors: Middleman AB, Robertson LM, DuRant RH, Chiou V, Emans SJ.

Year: 1997

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

DOI: 10.1016/s1083-3188(97)70084-6

PMID: 9391901

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.

DOI – publisher access (access restrictions may apply)

[C_PROTOCOL_D0436] Reproducible literature search strategy: Levonorgestrel

Original source / bibliographic reference

Authors: Europe PMC; documented search run

Year: 2026

Source type: Search strategy / screening protocol – not an individual study

Source access – 23 October 2026: Research protocol with machine-readable search results – not an individual study.

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