“Based on what I see for sale online, this has some of the highest quantity mgs of ingredients for the best possible price. Since my doc recommends this brand, I'm doubly sold.”
Calming L-theanine
A clean L-theanine supplement for calm, focused relaxation, without drowsiness.
- 200mg therapeutic dose per capsule
- Clinically studied for stress response
- Ideal for high-stress days and sleep
MOST SAVINGSFSA/HSA ELIGIBLE
Save an extra 5% with monthly delivery
- Free shipping
- Pause or cancel anytime
$40$42
Delivery
FSA/HSA ELIGIBLE
One-time purchase
- 5% subscription discount not applied
- Free shipping not included
Bundle & save $10Pair with Magnesium + Methyl B for full stress relief
$94$104
$94$104
- Promotes calm and relaxation without drowsiness
- Supports focus and mental clarity
- Helps the body manage daily stress
- Supports healthy sleep onset
- Promotes nervous system balance
- Supports healthy blood pressure
- Provides antioxidant support
- Non-habit forming and well-tolerated
Calming L-theanine
The science behind our ingredients
Calming L-theanine
Is this right for you?
Calming L-theanine
Is this right for you?
- 01You feel wired but want to stay sharp
L-theanine promotes a calm, focused mental state without drowsiness — making it useful during the workday when you need to take the edge off without losing focus.
- 02You're managing daily stress
L-theanine supports the body's stress response and helps modulate neurotransmitters involved in mood and relaxation, helping you feel more grounded through stressful days.
- 03You want a non-sedating sleep aid
Unlike melatonin, L-theanine doesn't force sleep. It promotes relaxation and helps quiet a busy mind, which can support more natural sleep onset for some people.
- 04You want a clean, single-ingredient option
No proprietary blends, no fillers, no stimulants. Just clinically dosed L-theanine — physician-formulated and third-party tested for purity.
01
You feel wired but want to stay sharp
L-theanine promotes a calm, focused mental state without drowsiness — making it useful during the workday when you need to take the edge off without losing focus.
02
You're managing daily stress
L-theanine supports the body's stress response and helps modulate neurotransmitters involved in mood and relaxation, helping you feel more grounded through stressful days.
03
You want a non-sedating sleep aid
Unlike melatonin, L-theanine doesn't force sleep. It promotes relaxation and helps quiet a busy mind, which can support more natural sleep onset for some people.
04
You want a clean, single-ingredient option
No proprietary blends, no fillers, no stimulants. Just clinically dosed L-theanine — physician-formulated and third-party tested for purity.
why we’re different
Not all supplements are created equal.
At Parsley, ‘professional grade’ means every supplement is third-party tested for quality and purity, and manufactured in NSF/USP-certified, cGMP-compliant U.S. facilities that meet FDA standards.
Our clinicians know which supplements actually move the needle — and which don't. Every formula is selected for clinical evidence, optimal bioavailability, and meaningful dosing. Not what's cheapest to manufacture. What actually works.
| Parsley Supplements | Standard Supplements | |
|---|---|---|
| Physician-Formulated | ||
| Third-Party Tested | ||
| Clinically Dosed | ||
| USA-Made | ||
| Most Bioavailable Forms |
When Covid hit, I experienced my first episode of anxiety - I knew what to take because Theanine had been helping my patients for over 15 years. It helps improve focus without any drowsiness, so it is my go to for ADHD as well.
Dawn Johnson, DO, ABOIM, IFMCP, MHA
Doctor
CUSTOMER REVIEWS
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Supplement FAQ
Parsley physicians have treated over 50,000 patients using a root-cause, functional medicine approach. That depth of practice informs every ingredient we select, every dose we use, and every formula we craft. The result is a standard most supplement brands can't meet: physician-formulated, third-party tested for purity and potency, clinically dosed, and manufactured in NSF/USP-certified, cGMP-compliant U.S. facilities that meet FDA standards.
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