Levodopa

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: Levodopa

Examples of brand names: Madopar [DE; combination]; Sinemet [USA; combination]

ATC code: N04BA01

Main use (for orientation): Parkinsonian syndromes

Documented research summary

CBD (rat, 2025) and THCV (mouse, 2020) reduced L-DOPA-induced dyskinesia preclinically. A small cannabis-extract crossover trial in 2004 (19 randomised, 17 completed) found no benefit for dyskinesia; this must not be interpreted as general safety. The nabilone pilot involved a synthetic agonist, not evidence for THC. Retrospective cannabis data and an individual case provide concomitant-medication context only.

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

3 separately recorded findings. Each statement applies to its documented study context.

CBD – laboratory and animal studies

Finding ID: B0481

Type of result: Context-specific finding

Observation: In the animal model, CBD reduced dyskinesia while preserving the levodopa motor effect studied.

Mechanism: Modulation of levodopa-induced dyskinesia.

Study type: 6-OHDA rat model, pharmacodynamics

Context studied: CBD 30 mg/kg, levodopa 10 mg/kg; PECS101 is a separately investigated molecule.

Clinical interpretation: Applicability to humans is unresolved; preclinical endpoint, not clinical evidence of treatment efficacy or safety.

Limitations and uncertainties: No human drug–drug interaction evidence or dosage recommendation; do not record the CBD derivative's effect as an effect of pure CBD.

Original sources for this finding: Cannabidiol improves L-DOPA-induced dyskinesia and modulates neuroinflammation and the endocannabinoid, endovanilloid and nitrergic systems. [VF_P_40684872]

THCV – laboratory and animal studies

Finding ID: B0482

Type of result: Context-specific finding

Observation: THCV reduced levodopa-induced dyskinesia in the model.

Mechanism: Modulation of levodopa-induced dyskinesia.

Study type: Pitx3 mouse model, pharmacodynamics

Context studied: THCV 2 mg/kg, two weeks; original abstract.

Clinical interpretation: Applicability to humans is unresolved; preclinical endpoint, not clinical evidence of treatment efficacy or safety.

Limitations and uncertainties: Not a clinical Parkinson's combination study; do not extrapolate the experimental dose.

Original sources for this finding: Beneficial effects of the phytocannabinoid Δ9-THCV in L-DOPA-induced dyskinesia in Parkinson's disease. [VF_P_32387338]

Oral cannabis extract – clinically studied

Finding ID: B0483

Type of result: Context-specific finding

Observation: No clear benefit against dyskinesia in this trial.

Mechanism: Investigation of the effect of a cannabis extract on levodopa-induced dyskinesia.

Study type: Randomised controlled human crossover trial

Context studied: 19 participants randomised, 17 completed; four-week treatment periods.

Clinical interpretation: Human endpoint directly studied under narrowly defined study conditions; long-term safety and generalisability not established.

Limitations and uncertainties: Neither an equivalence study nor a general safety study. Do not equate with subsequent animal findings for isolated CBD or THCV.

Original sources for this finding: Cannabis for dyskinesia in Parkinson disease: a randomized double-blind crossover study. [VF_P_15477546]

References and access status

[VF_L_D0417] CARBIDOPA-LEVODOPA (CARBIDOPA AND LEVODOPA) TABLET [ADVAGEN PHARMA LTD.,]

Original source / bibliographic reference

Authors: Marketing authorisation holder; official product information via DailyMed

Year: 2026

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_15477546] Cannabis for dyskinesia in Parkinson disease: a randomized double-blind crossover study.

Original source / bibliographic reference

Authors: Carroll CB, Bain PG, Teare L, Liu X, Joint C, Wroath C, Parkin SG, Fox P, Wright D, Hobart J, Zajicek JP.

Year: 2004

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

DOI: 10.1212/01.wnl.0000140288.48796.8e

PMID: 15477546

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[VF_P_32387338] Beneficial effects of the phytocannabinoid Δ9-THCV in L-DOPA-induced dyskinesia in Parkinson's disease.

Original source / bibliographic reference

Authors: Espadas I, Keifman E, Palomo-Garo C, Burgaz S, García C, Fernández-Ruiz J, Moratalla R.

Year: 2020

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

DOI: 10.1016/j.nbd.2020.104892

PMID: 32387338

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

Bibliographic attribution or source identity cross-checked.

DOI – publisher access (access restrictions may apply)

[VF_P_40684872] Cannabidiol improves L-DOPA-induced dyskinesia and modulates neuroinflammation and the endocannabinoid, endovanilloid and nitrergic systems.

Original source / bibliographic reference

Authors: Nascimento GC, Bálico GG, de Mattos BA, Dos-Santos-Pereira M, Oliveira IGC, Queiroz MEC, do Carmo Heck L, Navegantes LC, Guimarães FS, Del-Bel E.

Year: 2025

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

DOI: 10.1016/j.pnpbp.2025.111456

PMID: 40684872

Source access – 23 October 2026: Direct retrieval could not be fully verified; availability remains unresolved.

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