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Source Naturals

L-Phenylalanine, 100 Tablets

4.6 · 346 reviews
996 ₽

500 mg Dietary Supplement Free Form An Essential Amino Acid Suitable For Vegetarians L-Phenylalanine, an essential amino acid, is a precursor of the amino acid tyrosine and a whole series of neurotransmitters and hormones. Phenylalanine is first converted to tyrosine, which becomes L-dopa, which converts to norepinephrine, a key neurotransmitter and an adrenal hormone. L-Phenylalanine is also a direct precursor of PEA (phenylethylamine), another important neurotransmitter.

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500 mg Dietary Supplement Free Form An Essential Amino Acid Suitable For Vegetarians L-Phenylalanine, an essential amino acid, is a precursor of the amino acid tyrosine and a whole series of neurotransmitters and hormones. Phenylalanine is first converted to tyrosine, which becomes L-dopa, which converts to norepinephrine, a key neurotransmitter and an adrenal hormone. L-Phenylalanine is also a direct precursor of PEA (phenylethylamine), another important neurotransmitter.

Customer reviews

5.0
verified purchase
Excellent product

Phenylalanine is great for mood and muscle pain from fibromyalgia. I bought this because we like Source Naturals, but I realized it was actually the "DL" phenylalanine that I needed. I combine 1500 mgs. DL phenylalanine with 1500 mgs of tryptophan at night and sleep absolutely wonderful. I wake with only minimal pain from fibromyalgia. Really love it for that reason.

10/6/2010
5.0
verified purchase
Noticeable difference!

This supplement boosts mood and motivation from day 1! I originally got this to help reduce appetite and cravings for sweets and it definitely helps with that too. If you do intermittent fasting this is great to add to your morning coffee or take it before a workout. Don’t use at night however; due to it is quite energizing. This product really works well for me and I wish I’d have found it years ago!

3/8/2025
4.0
verified purchase
L-Phenylalanine, 500 mg

At first I have bought it to the dog, but then gave it to the elder woman. She has some thyroid and neuro issues. She evaluated it as good, but of course it did not done any miracle. It would be great it could have less modifications in additional ingredients.

9/28/2018
5.0
verified purchase
Helps me with motivation

I have SSRI induced apathy syndrome so i take it occasionally to boost motivation and it helps. I take it with capsule of D-phenylanine. I take it in the morning and before lunch

10/14/2024
5.0
verified purchase

Source Naturals L-Phenylalanine has become an essential part of my daily supplement regimen, and I'm incredibly impressed with its effectiveness and quality. As someone who prioritizes mental clarity and mood balance, I've experienced noticeable benefits since incorporating these tablets into my routine. Mood Support and Mental Clarity: One of the standout features of Source Naturals L-Phenylalanine is its ability to support mood balance and mental clarity. Phenylalanine is an essential amino acid that serves as a precursor to neurotransmitters like dopamine, norepinephrine, and epinephrine, which play key roles in regulating mood, focus, and cognitive function. Since starting these tablets, I've noticed a significant improvement in my overall mood and mental clarity, helping me feel more balanced and focused throughout the day.

3/8/2024
5.0
verified purchase

I have been taking this brand of phenylalanine for several years. After doing a lot of online research this brand consistently shows up as a top quality product. I have great confidence that this product is delivering the highest quality for my health.

2/23/2026
5.0
verified purchase
Great amino acid

Great quality, best ingredients and size is big 100 capsules and the smell is okay since it is a capsule it also helps with sleep and stress and mood also and doesn’t have a taste since it’s a capsule so overall very great product I would recommend it for it is benefit

11/9/2025
5.0
verified purchase
Quality is really good

I’ve been using this product for some time now. Love it’s affects and perfect dosage. Great size.

9/1/2025
5.0
verified purchase
Effective

Yes. The more I learn about amino acid therapy, the more I believe it is the key.

8/29/2025
5.0
verified purchase
Прекрасно!

I've been using Source Naturals L-Phenylalanine for a few weeks, and it's been a great addition to my daily routine. The 500 mg dosage provides just the right amount of support for mood and focus. I’ve noticed a significant improvement in my mental clarity and overall energy levels. The tablets are easy to swallow and have no aftertaste. This supplement is a reliable choice for anyone looking to enhance their cognitive function and well-being.

8/9/2025