APO-TRYPTOPHAN TABLET

Country: Canada

Language: English

Source: Health Canada

Active ingredient:

TRYPTOPHAN

Available from:

APOTEX INC

ATC code:

N06AX02

INN (International Name):

TRYPTOPHAN

Dosage:

750MG

Pharmaceutical form:

TABLET

Composition:

TRYPTOPHAN 750MG

Administration route:

ORAL

Units in package:

100

Prescription type:

Prescription

Therapeutic area:

ANTIDEPRESSANTS

Product summary:

Active ingredient group (AIG) number: 0111038005; AHFS:

Authorization status:

APPROVED

Authorization date:

2016-11-04

Summary of Product characteristics

Page 1 of 15
PRODUCT MONOGRAPH
APO-TRYPTOPHAN
L-TRYPTOPHAN TABLETS
250 MG, 500 MG, 750 MG AND 1 G
L-TRYPTOPHAN CAPSULES
500 MG
ADJUNCT IN THE MANAGEMENT OF AFFECTIVE DISORDERS
APOTEX INC.
DATE OF PREPARATION:
150 SIGNET DRIVE
December 4, 2003
TORONTO, ONTARIO
DATE OF REVISION:
M9L 1T9
November 2, 2016
CONTROL NO: 193855
Page 2 of 15
PRODUCT MONOGRAPH
APO-TRYPTOPHAN
L-Tryptophan Tablets
250 mg, 500 mg, 750 mg and 1 g
L-Tryptophan Capsules
500 mg
ADJUNCT IN THE MANAGEMENT OF AFFECTIVE DISORDERS
ACTION AND CLINICAL PHARMACOLOGY
The rationale for the use of L-tryptophan in affective disorders is
based on clinical
findings more than 20 years ago, that L-tryptophan increases 5-HT
(serotonin) synthesis
in the central nervous system of humans. It has been demonstrated in
clinical trials that
oral ingestion of L-tryptophan in humans caused a significant increase
in the level of the
serotonin metabolite, 5-hydroxyindoleacetic acid (5-HIAA), in the
lumbar cerebrospinal
fluid, indicating an increased turnover of serotonin in the CNS.
L-Tryptophan is one of the eight essential amino acids. The minimum
daily requirements
are said to be 0.25 g for males and 0.15 g for females. It is present
in the hydrolysates of
most proteins, the average western diet containing between 1 and 3
grams per day.
There are two major metabolic pathways for L-tryptophan, the first to
serotonin, the
second to nicotinic acid. Approximately 98% of dietary L-tryptophan is
metabolized into
nicotinic acid and only a very small amount is being metabolized to
serotonin via the
intermediary stage of 5-hydroxy-tryptophan (5-HTP). Tryptophan
hydroxylase, the
enzyme responsible for this step, is the rate-limiting enzyme for
serotonin production and
is normally only about half-saturated. Central nervous system
serotonin is metabolized by
monoamine oxidase to 5-HIAA.
Comparative Bioavailability
Tablets: A comparative bioavailability study was performed using
healthy human
volunteers. The rate and extent of absorption of L-tryptophan was
measured and
Page 3 of 15