Skip to content
Dr. Grey AI

Supplement

Violet Flower

Violet flower is the blossom of sweet violet, a plant used in traditional herbal remedies and rich in anthocyanin pigments and coumarin compounds with antioxidant and anti-inflammatory properties. People mostly look at it for cough, and in a double-blind trial of 182 children with asthma, coughing eased faster with violet syrup than with placebo alongside usual asthma medicine. Still, the evidence is limited, and other studies were small or lab-based.

Sources: PMID 25954025

Best evidence
Grade C
Conditions studied
3
Outcomes
6
Graded outcomes
0024

Evidence by condition

  • Strong
  • Moderate
  • Limited
  • Very limited

3 conditions, plus general outcomes

Allergic Rhinitis (Seasonal Allergies / Hay Fever)

Allergic Rhinitis (Seasonal Allergies / Hay Fever): outcomes studied for Violet Flower
GradeOutcomeEffectSizeStudiesPeopleStudies list
Allergic Rhinitis Symptoms

A double-blind randomized placebo-controlled clinical trial found that Viola odorata flower oil had significant positive effects on allergic rhinitis symptoms in adults, though the authors noted the study was preliminary and larger trials are needed.

Improves (the measure goes down)Small effect2 studies50 people

Studies that measured allergic rhinitis symptoms

Asthma

Asthma: outcomes studied for Violet Flower
GradeOutcomeEffectSizeStudiesPeopleStudies list
Asthma-Related Cough

A double-blind RCT in 182 children (ages 2-12) with intermittent asthma found that violet syrup as an adjunct to short-acting beta-agonist achieved 50% cough reduction and 100% cough suppression significantly faster than placebo (P<0.001).

Improves (the measure goes down)Moderate effect2 studies182 people

Studies that measured asthma-related cough

General

  • Antioxidant Activity: improves
  • Fever: improves
  • Insomnia: improves
General: outcomes studied for Violet Flower
GradeOutcomeEffectSizeStudiesPeopleStudies list
Antioxidant Activity

In vitro analysis found sweet violet flowers had the highest anthocyanin concentration (99.41 mg/100g) among tested edible flowers but relatively modest overall antioxidant capacity. Coumarin derivatives (umbelliferone, esculetin) with known anti-inflammatory and antioxidant properties were also identified.

Improves (the measure goes up)Small effect3 studies

Studies that measured antioxidant activity

Fever

A triple-blinded placebo-controlled RCT in 41 febrile neutropenic children with cancer found topical Viola odorata oil significantly reduced temperature at 30 minutes (P=0.005) and reduced rescue paracetamol use (5 vs 17 patients, P=0.001).

Improves (the measure goes down)Small effect2 studies41 people

Studies that measured fever

Insomnia

An uncontrolled pre-post study in 50 patients with chronic insomnia found intranasal violet oil drops reduced Insomnia Severity Index scores from 16.32 to 6.48 over one month (P<0.05). However, the lack of a control group limits interpretation.

Improves (the measure goes down)Moderate effect2 studies50 people

Studies that measured insomnia

Acute Respiratory Infection (ARI)

  • Respiratory Infection Symptoms: improves
Acute Respiratory Infection (ARI): outcomes studied for Violet Flower
GradeOutcomeEffectSizeStudiesPeopleStudies list
Respiratory Infection Symptoms

A randomized double-blind controlled trial in 108 COVID-19 outpatients found that add-on violet syrup significantly improved cough (P=0.025), myalgia (P=0.036), and headache (P=0.037) over 7 days compared to standard care alone.

Improves (the measure goes down)Small effect2 studies108 people

Studies that measured respiratory infection symptoms

Key findings

  • Allergic Rhinitis SymptomsAllergic Rhinitis (Seasonal Allergies / Hay Fever)Improves (the measure goes down)
  • Asthma-Related CoughAsthmaImproves (the measure goes down)
  • Antioxidant ActivityImproves (the measure goes up)

Shop Violet Flower

Third-party tested Violet Flower products. The evidence above is limited, so read it before you buy.

  • Grade C

Links to Fullscript, iHerb or Thorne carry our referral, so we may earn a commission at no extra cost to you. Grades come from the research and never change based on what we earn. Fullscript asks for a free account before it shows its catalog and prices. Full disclosure

Studies cited

8 studies from PubMed

  1. Efficacy and safety of add-on Viola odorata L. in the treatment of COVID-19: A randomized double-blind controlled trialJournal of Ethnopharmacology, 2023 · PMID 36535329
  2. Detection of Coumarin Derivatives of Viola odorata Cultivated in IraqJournal of Pharmacy and Bioallied Sciences, 2023 · PMID 37694059
  3. Impact of Drying Conditions on Antioxidant Activity of Red Clover (Trifolium pratense), Sweet Violet (Viola odorata) and Elderberry Flowers (Sambucus nigra)Materials (Basel, Switzerland), 2022 · PMID 35591648
  4. Efficacy of Sweet Violet (Viola odorata) flower oil on the symptoms of adults with allergic rhinitis: A double-blind randomized placebo-controlled clinical trialComplementary Therapies in Medicine, 2020 · PMID 32507426
  5. The Effect of Viola Odorata L. Oil for Fever in Children: A Randomized Triple-blinded Placebo-controlled Clinical TrialCurrent Drug Discovery Technologies, 2020 · PMID 31250761
  6. Analysis of Almond-Violet Oil by Gas Chromatography (A Traditional Formula)Iranian Journal of Medical Sciences, 2016 · PMID 27840468
  7. The Effect of Viola odorata Flower Syrup on the Cough of Children With Asthma: A Double-Blind, Randomized Controlled TrialJournal of Evidence-Based Complementary and Alternative Medicine, 2015 · PMID 25954025
  8. Efficacy of Viola odorata in Treatment of Chronic InsomniaIranian Red Crescent Medical Journal, 2014 · PMID 25763239