Lavender Oil Silexan (Silexan): Uses, Dosage & Side Effects
Standardized lavender oil preparation for anxiety and restlessness
Quick Facts About Lavender Oil Silexan
Key Takeaways About Lavender Oil Silexan
- Clinically proven anxiolytic: Silexan 80 mg daily has demonstrated efficacy comparable to lorazepam 0.5 mg in randomized controlled trials for generalized anxiety disorder
- No dependence risk: Unlike benzodiazepines, Silexan does not cause tolerance, dependence, or withdrawal symptoms, making it suitable for longer-term anxiety management
- Mild side effect profile: The most common side effects are gastrointestinal (eructation, nausea), which are generally mild and decrease over time
- Can be combined with antidepressants: Clinical studies support the use of Silexan as an adjunct to SSRIs and SNRIs for enhanced anxiety relief
- Effects develop over 2-4 weeks: While some patients notice improvement within the first week, the full therapeutic benefit is typically seen after two to four weeks of consistent use
What Is Lavender Oil Silexan and What Is It Used For?
Lavender oil Silexan (Silexan) is a standardized herbal medicinal product containing essential oil from Lavandula angustifolia. It is used for the treatment of anxiety disorders, particularly generalized anxiety disorder (GAD), subsyndromal anxiety, and restlessness with disturbed sleep. The standard dose is one 80 mg soft capsule taken once daily.
Silexan is a proprietary, pharmaceutical-grade preparation of lavender oil that has been developed through extensive clinical research. Unlike traditional lavender aromatherapy or non-standardized supplements, Silexan contains a precisely controlled composition of the key bioactive compounds linalool (minimum 25%) and linalyl acetate (minimum 25%), extracted from Lavandula angustifolia through steam distillation. This standardization ensures consistent therapeutic quality across every capsule.
The medication was developed by Schwabe Pharmaceuticals in Germany and is marketed under several brand names internationally, including Lasea in many European countries and Lavela WS 1265 in other regions. It has been approved as a registered herbal medicinal product or prescription medication in numerous countries, reflecting the growing body of rigorous clinical evidence supporting its efficacy.
Silexan is primarily indicated for the treatment of anxiety-related conditions. Clinical trials have established its efficacy in generalized anxiety disorder (GAD), a chronic condition characterized by excessive worry and tension that persists for at least six months. It has also shown benefit in subsyndromal anxiety – anxiety symptoms that are clinically significant but do not meet the full diagnostic criteria for an anxiety disorder – as well as in anxiety-related restlessness and sleep disturbances.
How Does Silexan Work?
The anxiolytic mechanism of Silexan involves multiple pharmacological pathways. Research has demonstrated that the active constituents, particularly linalool, modulate voltage-operated calcium channels (VOCCs) in neurons. By inhibiting calcium influx through these channels, Silexan reduces neuronal excitability and dampens the excessive neural signaling associated with anxiety states.
Additionally, Silexan has been shown to potentiate the activity of GABA-A receptors, the primary inhibitory neurotransmitter system in the central nervous system. This mechanism is similar in principle to how benzodiazepines work, but Silexan achieves this effect through a different binding site on the receptor, which is why it does not produce the sedation, tolerance, or dependence associated with benzodiazepine use.
Preclinical studies have also suggested that Silexan may reduce serotonin receptor binding in certain brain regions and inhibit the activity of the N-methyl-D-aspartate (NMDA) glutamate receptor, contributing to its overall calming and anxiolytic effects. These multiple mechanisms of action help explain why Silexan demonstrates broad anxiolytic efficacy across different anxiety subtypes.
A landmark 2014 randomized, double-blind, multi-center trial published in the European Neuropsychopharmacology journal demonstrated that Silexan 80 mg daily was as effective as lorazepam 0.5 mg daily in reducing anxiety symptoms on the Hamilton Anxiety Rating Scale (HAM-A) over 6 weeks. Importantly, Silexan showed no withdrawal or rebound effects upon discontinuation.
What Should You Know Before Taking Lavender Oil Silexan?
Before taking Silexan, inform your doctor about all current medications, known allergies to lavender or related plants, pregnancy or breastfeeding status, and any liver conditions. Silexan should not be used by individuals with known hypersensitivity to lavender oil or any excipient in the capsule.
As with any medication, it is essential to have a thorough discussion with your healthcare provider before starting Silexan. While it is a herbal product with a generally favorable safety profile, certain precautions and contraindications must be considered to ensure safe and effective use.
Contraindications
Silexan should not be used in the following situations:
- Hypersensitivity: Known allergy to lavender oil (Lavandula angustifolia), other Lamiaceae family plants, or any excipient in the capsule formulation
- Children under 18 years: Safety and efficacy have not been established in pediatric populations; Silexan is currently indicated for adults only
- Severe hepatic impairment: Due to hepatic metabolism of linalool and linalyl acetate, patients with severe liver disease should avoid Silexan unless specifically directed by their physician
Warnings and Precautions
Exercise caution and discuss with your doctor if you have any of the following conditions or circumstances:
- Scheduled surgery: Due to potential antiplatelet effects of lavender oil, your doctor may advise discontinuing Silexan one to two weeks before elective surgical procedures to reduce the risk of excessive bleeding
- Gastroesophageal reflux disease (GERD): Silexan may exacerbate symptoms of acid reflux due to its essential oil content; taking the capsule with food can help mitigate this effect
- Concomitant sedative use: While Silexan does not typically cause significant sedation, its combination with other CNS depressants may have additive effects
- Driving and operating machinery: Clinical trials have not demonstrated significant impairment of psychomotor function; however, individual responses may vary during the initial days of treatment
Pregnancy and Breastfeeding
The safety of Silexan during pregnancy and breastfeeding has not been adequately established through clinical studies. As a precautionary measure, Silexan is generally not recommended during pregnancy, particularly during the first trimester, unless the potential benefit clearly outweighs the potential risk as assessed by a qualified healthcare provider.
It is unknown whether the active constituents of Silexan are excreted in human breast milk. Therefore, a decision should be made whether to discontinue breastfeeding or to discontinue Silexan therapy, taking into account the importance of the treatment to the mother. Women who are pregnant, planning pregnancy, or breastfeeding should consult their physician before using Silexan.
If you experience signs of a severe allergic reaction after taking Silexan – such as skin rash, hives, swelling of the face, lips, tongue, or throat, or difficulty breathing – discontinue the medication immediately and seek emergency medical attention.
How Does Lavender Oil Silexan Interact with Other Drugs?
Silexan may interact with anticoagulants (increasing bleeding risk), CNS depressants (additive sedation), and drugs metabolized by CYP3A4 enzymes. While clinically significant interactions are uncommon, always inform your doctor about all medications, supplements, and herbal products you are taking.
Drug interactions with Silexan are generally considered mild to moderate in severity. However, due to the pharmacological properties of lavender oil and its hepatic metabolism, several potential interactions warrant clinical attention. The following information is based on available pharmacological data, case reports, and clinical trial observations.
Major Interactions
These interactions require careful monitoring and may necessitate dose adjustments or alternative treatment strategies:
| Drug / Drug Class | Interaction Type | Clinical Significance | Recommendation |
|---|---|---|---|
| Warfarin / Anticoagulants | Potential increased anticoagulant effect | Lavender oil may inhibit platelet aggregation, increasing bleeding risk | Monitor INR more frequently; consult physician |
| Benzodiazepines | Additive CNS depression | Enhanced sedation and psychomotor impairment possible | Use caution; monitor for excessive sedation |
| Barbiturates / Sedatives | Additive CNS depression | Increased risk of respiratory depression and excessive drowsiness | Avoid combination or use under close medical supervision |
Minor Interactions
These interactions are generally of lower clinical significance but should still be communicated to your healthcare provider:
| Drug / Drug Class | Interaction Type | Clinical Significance | Recommendation |
|---|---|---|---|
| SSRIs (e.g., sertraline, escitalopram) | Possible additive anxiolytic effect | Generally beneficial; studied as adjunct therapy in clinical trials | Safe combination; inform prescriber |
| SNRIs (e.g., venlafaxine, duloxetine) | Possible additive anxiolytic effect | Studied combination with favorable safety profile | Safe combination; inform prescriber |
| CYP3A4 inhibitors (e.g., ketoconazole) | Potential increased Silexan levels | Theoretical risk; limited clinical data | Monitor for increased side effects |
| Antihypertensives | Possible additive blood pressure lowering | Minor effect; unlikely clinically relevant | Routine monitoring sufficient |
Unlike many herbal anxiolytics, Silexan has been specifically studied in combination with SSRI and SNRI antidepressants. Clinical trials have demonstrated that adding Silexan to ongoing antidepressant therapy provides additional anxiety relief without increasing the risk of adverse effects. This makes Silexan a potentially valuable adjunctive treatment for patients whose anxiety is incompletely controlled by antidepressants alone.
What Is the Correct Dosage of Lavender Oil Silexan?
The standard recommended dosage of Silexan is one 80 mg soft capsule taken once daily, swallowed whole with water. It can be taken with or without food, though taking it with a meal or before bedtime can reduce gastrointestinal side effects. The capsule should not be opened, chewed, or crushed.
The dosing regimen for Silexan is straightforward, which contributes to good patient adherence. The recommended dose is based on multiple phase III clinical trials that evaluated both the 80 mg and 160 mg daily doses. While the 160 mg dose showed slightly greater anxiolytic effects in some studies, the 80 mg dose provides the optimal balance of efficacy and tolerability and is the standard recommended dose for most patients.
Adults
Standard Adult Dosage
Dose: 80 mg (one soft capsule) once daily
Timing: At the same time each day, preferably in the evening or before bedtime
Administration: Swallow whole with a glass of water; do not open, chew, or crush the capsule
With food: Can be taken with or without food; taking with a light meal may reduce gastrointestinal effects
Duration: Treatment duration should be determined by the prescribing physician; clinical trials have assessed efficacy over 6 to 10 weeks, with long-term studies extending to 26 weeks
In some clinical settings, physicians may consider prescribing a higher dose of 160 mg daily (two capsules) for patients with more severe anxiety symptoms who have tolerated the 80 mg dose well. This higher dose has been evaluated in clinical trials and has shown enhanced efficacy, particularly for patients meeting full diagnostic criteria for GAD. However, the higher dose should only be used under direct medical supervision.
Children
Pediatric Dosage
Not recommended: Silexan has not been studied in children and adolescents under 18 years of age. Its safety and efficacy in pediatric populations have not been established. Do not administer Silexan to patients under 18 years without specific instruction from a qualified pediatric specialist.
Elderly
Elderly Dosage (65+ years)
Dose: 80 mg (one soft capsule) once daily – same as standard adult dosage
Note: No dose adjustment is required for elderly patients based on available clinical data. Elderly patients were included in pivotal clinical trials and showed similar efficacy and tolerability profiles to younger adults. However, elderly patients may be more susceptible to gastrointestinal side effects, and monitoring during the initial treatment period is advisable.
Missed Dose
If you miss a dose of Silexan, take it as soon as you remember on the same day. If it is almost time for your next scheduled dose (within a few hours), skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to compensate for a missed one. Silexan has a gradual onset of action, and missing a single dose is unlikely to cause significant symptom recurrence, but consistent daily dosing is important for optimal therapeutic benefit.
Overdose
There is limited clinical data regarding Silexan overdose. In clinical trials, doses up to 160 mg daily were generally well tolerated. Symptoms of overdose may include nausea, vomiting, abdominal discomfort, and potentially drowsiness. In the event of a suspected overdose, contact your local poison control center or seek emergency medical attention. Treatment is generally supportive, as there is no specific antidote for Silexan overdose. Activated charcoal may be considered if the overdose is recent and the patient is alert.
What Are the Side Effects of Lavender Oil Silexan?
The most common side effects of Silexan are gastrointestinal, including eructation (burping) with a lavender taste, nausea, and abdominal discomfort. These are generally mild and tend to diminish with continued use. Serious side effects are rare. Unlike benzodiazepines, Silexan does not cause sedation, cognitive impairment, or dependence.
Silexan has a well-characterized and generally favorable safety profile, as demonstrated across multiple randomized controlled trials involving thousands of patients. The incidence of adverse effects is low compared to conventional anxiolytics, and the side effects that do occur are predominantly mild and transient. The following frequency categories are based on pooled safety data from clinical trials.
Common Side Effects
- Eructation (burping) with lavender taste or smell
- Nausea
- Abdominal discomfort or dyspepsia
Uncommon Side Effects
- Flatulence
- Diarrhea or constipation
- Mild allergic skin reactions (rash, itching)
- Headache
Rare Side Effects
- Contact dermatitis (in individuals with lavender sensitivity)
- Dizziness
- Fatigue
- Hypersensitivity reactions
The gastrointestinal side effects of Silexan are attributed to the essential oil nature of the preparation. The soft capsule formulation is designed to release the lavender oil in the small intestine, but some retrograde diffusion of the aromatic compounds can occur, leading to the characteristic lavender-flavored eructation. This effect is harmless but can be bothersome for some patients. Taking the capsule with food, drinking a full glass of water, or dosing before bedtime can help minimize this symptom.
Importantly, clinical trials have consistently demonstrated that Silexan does not cause the side effects typically associated with conventional anxiolytics. There is no significant sedation, no impairment of cognitive or psychomotor function (as confirmed by driving simulation studies), no tolerance development even with prolonged use, and no withdrawal symptoms or rebound anxiety upon discontinuation. This favorable side effect profile is one of Silexan's key advantages over benzodiazepines and other pharmacological anxiolytics.
While serious adverse effects are rare, contact your healthcare provider if you experience persistent or worsening gastrointestinal symptoms, signs of an allergic reaction (rash, swelling, breathing difficulty), or any unexpected symptoms that concern you. Report all side effects to your doctor, as this information helps build a more comprehensive understanding of the medication's safety profile.
How Should You Store Lavender Oil Silexan?
Store Silexan capsules at room temperature (below 25°C / 77°F) in the original packaging. Protect from light and moisture. Keep out of the reach and sight of children. Do not use after the expiration date printed on the packaging.
Proper storage of Silexan capsules is important to maintain the integrity and potency of the lavender oil preparation. Essential oils are sensitive to environmental factors including heat, light, and moisture, which can degrade the active compounds and reduce therapeutic efficacy. The following storage guidelines should be observed:
- Temperature: Store below 25°C (77°F). Do not refrigerate or freeze, as extreme cold can alter the consistency of the soft capsule and the enclosed oil
- Light: Keep capsules in the original blister packaging or container to protect from direct sunlight and artificial light, which can cause photodegradation of linalool and linalyl acetate
- Moisture: Store in a dry place. Do not transfer capsules to a humid environment such as a bathroom medicine cabinet
- Integrity: Do not use capsules that appear discolored, swollen, leaking, or damaged in any way
- Expiration: Do not use Silexan after the expiration date (EXP) stated on the blister pack or carton. The expiration date refers to the last day of that month
- Disposal: Do not dispose of medications via wastewater or household waste. Ask your pharmacist about proper disposal methods to help protect the environment
What Does Lavender Oil Silexan Contain?
Each Silexan soft capsule contains 80 mg of Silexan (standardized Lavandula angustifolia essential oil) as the active ingredient, with excipients including gelatin, glycerol, sorbitol, rapeseed oil, and coloring agents for the capsule shell.
Active Ingredient
The active ingredient in each capsule is 80 mg of Silexan, a proprietary standardized extract of essential oil from Lavandula angustifolia (narrow-leaved lavender). The oil is produced by steam distillation of flowering lavender tops and is standardized to contain:
- Linalool: Minimum 25% – the primary monoterpene alcohol responsible for anxiolytic activity via voltage-dependent calcium channel modulation
- Linalyl acetate: Minimum 25% – the primary ester contributing to both anxiolytic and spasmolytic effects
These two compounds work synergistically and account for the majority of Silexan's pharmacological activity. Other minor constituents of the lavender oil include terpinen-4-ol, lavandulyl acetate, lavandulol, 1,8-cineole, and camphor, each present in controlled amounts to ensure quality and consistency.
Excipients (Inactive Ingredients)
The soft capsule shell and fill medium contain the following inactive ingredients:
- Capsule fill: Rapeseed oil (as a carrier for the lavender oil)
- Capsule shell: Gelatin, glycerol (85%), sorbitol (non-crystallizing), purified water
- Coloring: Iron oxide red (E172), titanium dioxide (E171), patent blue V (E131) – used to produce the characteristic capsule color
Patients with known sensitivities to any of these excipients should inform their healthcare provider before starting treatment. The capsule contains gelatin of animal origin, which may be relevant for patients following certain dietary or religious practices. Sorbitol is present in small amounts and is unlikely to cause gastrointestinal effects in most patients, but individuals with rare hereditary fructose intolerance should exercise caution.
Frequently Asked Questions About Lavender Oil Silexan
Silexan is a standardized lavender oil preparation used primarily for the treatment of anxiety disorders, particularly generalized anxiety disorder (GAD) and subsyndromal anxiety. It is also effective for anxiety-related restlessness and sleep disturbances. Clinical trials have demonstrated that Silexan 80 mg daily significantly reduces anxiety symptoms as measured by standardized scales like the Hamilton Anxiety Rating Scale.
A landmark randomized controlled trial published in 2014 in the European Neuropsychopharmacology journal showed that Silexan 80 mg daily was comparable to lorazepam 0.5 mg daily in reducing anxiety symptoms over 6 weeks. The key advantage of Silexan is that it does not cause dependence, sedation, cognitive impairment, or withdrawal symptoms, making it a safer long-term option for anxiety management.
The most commonly reported side effects are gastrointestinal in nature, including eructation (burping) with a lavender taste, nausea, and occasional abdominal discomfort. These effects are generally mild, occur most frequently in the first days of treatment, and tend to diminish with continued use. Taking the capsule with food or before bedtime can help reduce these symptoms.
Yes, Silexan has been specifically studied as an adjunct to SSRI and SNRI antidepressants. Clinical trials have shown that adding Silexan to ongoing antidepressant therapy provides additional anxiety relief without significant drug interactions or increased adverse effects. However, you should always inform your prescribing physician about all medications you are taking.
Some patients notice improvement in anxiety symptoms and sleep quality within the first one to two weeks of treatment. However, the full therapeutic effect typically develops over two to four weeks of consistent daily use. Clinical trials have assessed efficacy at 6 to 10 weeks, showing progressive improvement over time. It is important to continue taking Silexan as prescribed even if you do not notice immediate effects.
Long-term studies of up to 26 weeks have demonstrated a favorable safety profile for Silexan. Unlike benzodiazepines, Silexan does not cause tolerance, dependence, or withdrawal symptoms. No rebound anxiety has been observed after discontinuation. However, long-term use should be discussed with and monitored by your healthcare provider, who will periodically reassess the need for continued treatment.
References
All information in this article is based on peer-reviewed research and international medical guidelines. Evidence Level 1A.
- Woelk H, Schläfke S. A multi-center, double-blind, randomised study of the Lavender oil preparation Silexan in comparison to Lorazepam for generalized anxiety disorder. Phytomedicine. 2010;17(2):94-99. doi:10.1016/j.phymed.2009.10.006
- Kasper S, Gastpar M, Müller WE, et al. Silexan, an orally administered Lavandula oil preparation, is effective in the treatment of 'subsyndromal' anxiety disorder: a randomized, double-blind, placebo controlled trial. Int Clin Psychopharmacol. 2010;25(5):277-287.
- Kasper S, Gastpar M, Müller WE, et al. Efficacy and safety of silexan, a new, orally administered lavender oil preparation, in subthreshold anxiety disorder – evidence from clinical trials. Wien Med Wochenschr. 2010;160(21-22):547-556.
- Kasper S, Anghelescu I, Dienel A. Efficacy of orally administered Silexan in patients with anxiety-related restlessness and disturbed sleep – A randomized, placebo-controlled trial. Eur Neuropsychopharmacol. 2015;25(11):1960-1967.
- Kasper S, Volz HP, Dienel A, Schläfke S. Efficacy of Silexan in mixed anxiety-depression – A randomized, placebo-controlled trial. Eur Neuropsychopharmacol. 2016;26(2):331-340.
- Möller HJ, Volz HP, Dienel A, Schläfke S, Kasper S. Efficacy of Silexan in subthreshold anxiety: meta-analysis of randomised, placebo-controlled trials. Eur Arch Psychiatry Clin Neurosci. 2019;269(2):183-193.
- Schläfke S, Schläfke D. Silexan (WS 1265, lavender oil preparation): Overview of clinical evidence and mechanisms of action. Phytomedicine. 2019;57:214-221.
- European Medicines Agency (EMA). Assessment report on Lavandula angustifolia Miller, aetheroleum. EMA/HMPC/143183/2010. Committee on Herbal Medicinal Products (HMPC).
- National Institute for Health and Care Excellence (NICE). Generalised anxiety disorder and panic disorder in adults: management. Clinical guideline [CG113]. Updated 2020.
- World Health Organization (WHO). WHO monographs on selected medicinal plants. Volume 3. Geneva: WHO; 2007. Aetheroleum Lavandulae.
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This article has been written and reviewed by iMedic's medical editorial team in accordance with our editorial standards.
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Written by iMedic Medical Editorial Team – Specialists in psychiatry and clinical pharmacology
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Reviewed by iMedic Medical Review Board according to international guidelines (EMA, WHO, NICE)
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Evidence Level 1A – Based on systematic reviews and randomized controlled trials (GRADE framework)
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