SKU: 96348244375

Thorne 5-Hydroxytryptophan (Formerly Griffonia) 90 Capsules

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Description

Thorne 5-Hydroxytryptophan (Formerly Griffonia) 90 CapsulesThorne 5 Hydroxytryptophan (Formerly Griffonia) 90 Capsules 5 Hydroxytryptophan (5 HTP) is the intermediate metabolite produced when the body initiates the process of converting the essential amino acid L tryptophan to serotonin.* Serotonin levels in the body are associated with the regulation of sleep, mood, aggression, appetite, temperature, sexual behavior, and pain sensation.* Supplementing with 5 HTP to facilitate serotonin production is

Thorne 5-Hydroxytryptophan (Formerly Griffonia) 90 Capsules

5-Hydroxytryptophan (5-HTP) is the intermediate metabolite produced when the body initiates the process of converting the essential amino acid L-tryptophan to serotonin.* Serotonin levels in the body are associated with the regulation of sleep, mood, aggression, appetite, temperature, sexual behavior, and pain sensation.*

Supplementing with 5-HTP to facilitate serotonin production is preferable to supplementing with L-tryptophan because, unlike L-tryptophan, 5-HTP cannot be shunted into niacin or protein production. Supplementation with 5-HTP bypasses the conversion of L-tryptophan into 5-HTP by the enzyme tryptophan hydroxylase, the rate-limiting step in the synthesis of serotonin and a step that can be inhibited by a number of factors, including stress, insulin resistance, increasing age, and deficiencies of vitamin C, folate, and iron.*

Intestinal absorption of 5-HTP does not require the presence of a transport molecule and is not affected by the presence of other amino acids; therefore, it may be taken with meals without reducing its effectiveness.* 5-HTP easily crosses the blood-brain barrier and effectively increases central nervous system (CNS) synthesis of serotonin.*

To further facilitate serotonin production, Thorne Research's 5-HTP formula contains pyridoxal 5'-phosphate, the active form of vitamin B6 which is a cofactor for the conversion of 5-HTP to serotonin.* 5-HTP is commercially produced by extraction from the seeds of the African plant, Griffonia simplicifolia.

*Disclaimer

These statements have not been evaluated by Health Canada or the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

Please be advised: Thorne Research is a professional line and can only be sold under the recommendation and supervision of a practitioner.


Nutrition Facts
Serving Size: 2 Capsules



Amount Per Serving



% Daily Value *
Vitamin B6 (as Pyridoxal 5'-Phosphate) 6.8 mg 340%
5-Hydroxytryptophan 100 mg *
* Percent daily values are based on a 2000 calorie diet
† Daily Value not established
Note: Serving Sizes are rounded to the nearest whole serving

Other Ingredients: Microcrystalline Cellulose, Hypromellose (derived from cellulose) capsule, Leucine, Silicon Dioxide.

Recommended Use: Adults: Take with food.

To promote healthy mood balance: Take 1-2 capsules three times daily or as recommended by a health-care practitioner. To minimize the risk of gastrointestinal side effects, start dosing at 1 capsule three times daily and slowly increase to effective dose over a period of 2 weeks.

For use as a sleep aid: Take 2-4 capsules daily or as recommended by a health-care practitioner. Take 30-45 minutes before bedtime.

Warning: Consult a health-care practitioner prior to use: if you are pregnant or breastfeeding; if symptoms persist or worsen; if sleeplessness persists continuously for more than 3 weeks (chronic insomnia). Consult a health-care practitioner prior to use if you are taking carbidopa or drugs/supplements with serotonergic activity. These may include, but are not limited to, L-tryptophan, S-adenosylmethionine (SAMe), St. John’s wort, antidepressants, pain killers, over the counter cough and cold medication containing dextromethorphan, anti-nausea medication and anti-migraine medication. Some people may experience diarrhea, nausea, vomiting, and abdominal pain. Discontinue use and consult a health-care practitioner if you show signs of weakness, oral ulcers, or abdominal pain accompanied by severe muscle pain or if you experience skin changes. Do not use if you have scleroderma. Some people may experience drowsiness. Exercise caution if operating heavy machinery, driving a motor vehicle or are involved in activities requiring mental alertness.

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SKU: 96348244375

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Jennifer L Cremata
Louisville, US
★★★★★ 5
Very healing
I bought this for face but had also heard that this can be used for other skin issues. Yesterday, I cut my index finger with a label remover (basically a razor blade). Once I stopped the bleeding, I kept it clean and covered for a bit. Before bed, I decided to put a dab of this on my cut, when I woke up this morning, it's like a miracle! It barely hurts and looks quite healed!
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Reviewed in the United States on May 20, 2026
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DWF
Lexington, US
★★★★★ 5
It works... very well... for me. VERY WELL.
I typically detest American companies as many of the products contain both harmful and helpful ingredients at the same time. So far, Prequel has EXCEEDED my expectations. PROS: It works for my skin. EWG gives good scores to Prequel also. Skin looks great afterwards. No scent. Lasts for hours with a healthy skin tone. You don't have to use a lot to cover an area (see below). CONS: Slightly greasy when applied so it not a lightweight cream. Small tube (see below). Pricey. You don't have to use a lot. I find that due to its slightly greasy nature, you can use much less to cover a greater area. Afterwards the greasiness disappears, leaving plump, healthy feeling skin texture. As with any skincare product, your skin may react differently. I have tried major Western brands which worsened my skin (Cereva for instance) before switching to Korean & Japanese products (far superior). Prequel is now the only Western brand I will use on a regular basis, to include their bar of soap (superior to my regular Korean brand).
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Reviewed in the United States on September 14, 2025
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UrbanUtah
San Leandro, US
★★★★★ 5
Great dry spot treatment!
Worked wonders on winter dry patches on my cheeks and sides of mouth. I’m a somewhat new Prequel product user. I follow the creator on YouTube and love her skincare videos. I have tried a few products so far and have been happy with the results. I just ordered the foot repair ointment for my husband as well. I think this brand is a great value for the money. I have not had any bad reactions so far and I have VERY sensitive skin. This ointment is lightweight and melts into my skin well and the next morning my dry spots were literally invisible. It’s fragrance free, I did not notice any scent at all, which is importance to me.
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Reviewed in the United States on January 3, 2026
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gina
San Leandro, US
★★★★★ 4
Prequel is always great
Very soothing and calming for skin. Tube lasted a long time. I have sensitive skin and often have reactions but did great with this.
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Reviewed in the United States on March 14, 2026
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Kitkat
Fort Morgan, US
★★★★★ 5
This is a barrier cream?
I also have very oily skin, so normally I stay away from anything that says barrier or balm. I push skin a lot lol...with max strength tretinoin, glycolic acids, salicylic acids, vitamin C... so there are times when I just need max help from a richer product bc sometimes I take it too far. LRP Cicaplast has been a staple and has saved me many a times. I bought this bc of the high percentage of ectoin, 5%, and it was so reasonably priced. When I squeezed the tube, I was really worried, it was thicker looking than the Cicaplast. However, when I spread it out, it was SO light and a tiny amount --barely a pea size, was enough to coat my face. It did not feel heavy. Even with my oily skin, I think I could wear this everyday. As an experiment, I applied any excess on one side of my hand, as I'm right handed, I would apply it on my left hand. I've had this about a week, and right now after doing the dishes, and washing my hands multiple times without any hand cream on it, my right hand is definitely drier than my left hand. My left hand also looks less red and more calm. This formula is 5 stars for both the effectiveness and the elegant formula. It may yet replace my LRP Cicaplast...we'll see!
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Reviewed in the United States on November 6, 2025

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