L-tryptophan - Codeine Phosphate, Pseudoephedrine, Triprolidine Interaction
Herbal: L-tryptophan
Also Known As: L-Triptofano, L-Trypt, L-Tryptophane, Tryptophan
Drug: Codeine Phosphate, Pseudoephedrine, Triprolidine
Brand names:
CoActifed
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 25, 2025
Interaction Details
Codeine Phosphate, Pseudoephedrine, Triprolidine is classified as belonging to the following category: Cns Depressants
Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Clinical research shows that L-tryptophan can cause fatigue and drowsiness.
Interaction Rating
Likelihood of Occurrence
ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
References
- Lieberman HR, Corkin S, Spring BJ. The effects of dietary neurotransmitter precursors on human behavior. Am J Clin Nutr 1985;42:366-70.
L-tryptophan Overview
L-tryptophan is an essential amino acid found in proteins. "Essential" amino acids are not produced in our bodies and must obtained from the diet. L-tryptophan is commonly used as a dietary supplement to help with sleep and mood disorders, and is a precursor to the neurotransmitter serotonin. Serotonin is involved in the regulation of sleep, mood, and other functions.
L-tryptophan - More Interactions
L-tryptophan interacts with 390 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
Return to the main supplement interaction checker page
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
Ask A Pharmacist About Your Herbal Questions!
Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
Ask A Pharmacist