5-HTP

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This monograph is intended to serve as a guide to industry for the preparation of Product Licence Applications (PLAs) and labels for natural health product market authorization. It is not intended to be a comprehensive review of the medicinal ingredient.

Notes

• Text in parentheses is additional optional information which can be included on the PLA and product label at the applicant's discretion.
• The solidus (/) indicates that the terms and/or statements are synonymous. Either term or statement may be selected by the applicant.

Date

April 26, 2024

Proper name(s), Common name(s), Source information

Table 1. Proper name(s), Common name(s), Source information

Proper name(s)	Common name(s)	Source information
		Source ingredient(s)	Source material(s)	Part(s)
5-Hydroxy-L-tryptophan L-5-Hydroxytryptophan	L-5-HTP L-5-Hydroxytryptophan	N/A	Griffonia simplicifolia	Seed
		L-5-HTP1	N/A	N/A
		N/A	Escherichia coli	Whole cell for biosynthesis
		N/A	Saccharomyces cerevisiae	Whole cell for biosynthesis

References: Proper names: RSC 2023; Common names: RSC 2023; Source information: Lemaire and Adosraku 2002, Fellows and Bell 1970.

¹Synthetic

Route of Administration

Oral

Dosage Form(s)

This monograph excludes foods or food-like dosage forms as indicated in the Compendium of Monographs Guidance Document.

Acceptable dosage forms for oral use are indicated in the dosage form drop-down list of the web-based Product Licence Application form for Compendial applications.

Use(s) or Purpose(s)

• Helps (to) promote healthy mood balance (Pöldinger et al. 1991; Zmilacher et al. 1988; Nakajima et al. 1978).
• Helps (to) relieve sleep disturbances associated with mood imbalance (Sutanto et al. 2024; Poldinger et al. 1991; Soulairac and Lambinet 1988)
• Helps (to) relieve symptoms of fibromyalgia (Nicolodi and Sicuteri 1996; Sarzi Puttini and Caruso 1992; Caruso et al. 1990).
• Helps (to) reduce the severity and duration of migraine headaches when taken as a preventative (prophylactic) (Titus et al. 1986; Bono et al. 1984; Sicuteri 1973).
• To be used with a program of reduced intake of dietary calories and increased physical activity (if possible) to help in weight management by reducing carbohydrate cravings (Cangiano et al.1998; Cangiano et al. 1992; Ceci et al. 1989).

Dose(s)

Subpopulation(s)

Adults 18 years and older

Quantity(ies)

Healthy mood balance

150 - 300 milligrams of 5-HTP, per day (Pöldinger et al. 1991; Nakajima et al. 1978).

Fibromyalgia symptoms

300 - 400 milligrams of 5-HTP, per day; Not to exceed 300 milligrams per single dose (Nicolodi and Sicuteri 1996; Caruso et al. 1990).

Migraine prophylaxis

200 - 600 milligrams of 5-HTP, per day; Not to exceed 300 milligrams per single dose (Titus et al. 1986; Sicuteri 1973).

Weight management

750 - 900 milligrams of 5-HTP, per day; Not to exceed 300 milligrams per single dose (Cangiano et al. 1998; Cangiano et al. 1992; Ceci et al. 1989).

Sleep disturbances

100 - 200 milligrams of 5-HTP, per day (Sutanto et al. 2024; Soulairac and Lambinet 1988; Soulairac and Lambinet 1977; Wyatt et al. 1971).

Direction(s) for use

All uses

To minimize the risk of gastrointestinal side effects, start at lower dose and slowly increase to effective dose over 2-week period (Birdsall 1998).

All uses (excluding weight management)

Take with food (Pöldinger et al. 1991).

Weight management

Take 30 minutes before meals (Cangiano et al. 1998; Cangiano et al. 1992; Ceci et al. 1989).

Duration(s) of Use

Healthy mood balance; Fibromyalgia symptoms; Migraine prophylaxis; Sleep disturbances

Use for at least 2 weeks to see beneficial effects (Jangid et al. 2013; Caruso et al. 1990; Nakajima et al. 1978; Sicuteri 1973).

Weight management (products providing over 600 mg 5-HTP, per day)

Ask a health care practitioner/health care provider/health care professional/doctor/physician for use beyond 12 weeks (Cangiano et al. 1992).

Risk Information

Caution(s) and warning(s)

All uses

• Ask a health care practitioner/health care provider/health care professional/doctor/physician before use if you are taking carbidopa or health products with serotonergic activity such as mood balance supplements, cough medication containing dextromethorphan, pain killers or medications for nausea or migraine (Mayo Clinic Staff 2022; Patel and Marzella 2017; Turner et al 2006).
• When using this product exercise caution while driving or using machinery, as you may experience drowsiness (Berardi et al. 2002).
• Ask a health care practitioner/health care provider/health care professional/doctor/physician if symptoms persist or worsen.

All uses (excluding weight management)

Ask a health care practitioner/health care provider/health care professional/doctor/ physician before use if you are pregnant or breastfeeding.

Weight management

Ask a health care practitioner/health care provider/health care professional/doctor/ physician before use if you are breastfeeding.

Healthy mood balance; Fibromyalgia symptoms

Ask a health care practitioner/health care provider/health care professional/doctor/physician before use if you have a psychological disorder such as anxiety or depression.

Contraindication(s)

All products

• Do not use if you have scleroderma (Lampert et al. 1992; Sternberg et al. 1980).
• Do not use if you are taking antidepressants (Mayo Clinic Staff 2022; Patel and Marzella 2017).

Weight management

Do not use if you are pregnant (HC 2010).

Known adverse reaction(s)

• When using this product you may experience gastrointestinal discomfort/disturbances (Turner et al. 2006; Byerley et al. 1987).
• Stop use and ask a health care practitioner/health care provider/health care professional/doctor/physician if you experience skin hardening, pain or stiffness of muscles or joints, tremors, agitation/confusion, or an increased heart rate (Boyer 2023; Varga 2023; Mayo Clinic Staff 2022; Patel and Marzella 2017; Das et al. 2004; Erner et al. 2003; Lampert et al. 1992; Sternberg et al. 1980).

Non-medicinal ingredients

Must be chosen from the current Natural Health Products Ingredients Database (NHPID) and must meet the limitations outlined in the database.

Storage conditions

Must be established in accordance with the requirements described in the Natural Health Products Regulations.

Specifications

• The finished product specifications must be established in accordance with the requirements described in the Natural and Non-prescription Health Products Directorate (NNHPD) Quality of Natural Health Products Guide.
• The medicinal ingredient must comply with the requirements outlined in the NHPID.

EXAMPLE OF PRODUCT FACTS:

Consult the Guidance Document, Labelling of Natural Health Products for more details.

References Cited

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References Reviewed

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