Serotonin hydrochloride


5-HT, 3-(2-Aminoethyl)-5-hydroxyindole hydrochloride, 5-Hydroxytryptamine hydrochloride
Empirical Formula (Hill Notation):
C10H12N2O · HCl
CAS Number:
Molecular Weight:
Beilstein/REAXYS Number:
MDL number:
PubChem Substance ID:

Quality Level






white to off-white


149-154 °C (lit.)


H2O: 17 mg/mL
0.1 M HCl: 22 mg/mL
ethanol: 5.3 mg/mL

storage temp.


SMILES string




InChI key


Gene Information

human ... HTR3A(3359)

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25 mg in poly bottle
1 g in glass bottle
100, 250 mg in glass bottle

Biochem/physiol Actions


Features and Benefits

This compound is also offered as part of Sigma′s Library of Pharmacologically Active Compounds (LOPAC®1280), a biologically annotated collection of high-quality, ready-to-screen compounds. Click here to learn more.
This compound is featured on the Biogenic Amine Transporters page of the Handbook of Receptor Classification and Signal Transduction. To browse other handbook pages, click here.

Preparation Note

Solutions should be freshly prepared.

Legal Information

LOPAC is a registered trademark of Sigma-Aldrich Co. LLC


Exclamation mark




Acute Tox. 4 Dermal - Acute Tox. 4 Inhalation - Acute Tox. 4 Oral - Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3

Target Organs

Respiratory system


11 - Combustible Solids

WGK Germany


Flash Point F

Not applicable

Flash Point C

Not applicable

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves

Certificate of Analysis

Certificate of Origin

  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  3. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  4. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  5. Can I store solutions of Product H9523, Serotonin hydrochloride?

    Solutions of this product are unstable.  We recommend preparing this solution fresh for each application.

  6. Is Product H9523, Serotonin hydrochloride, the neurotransmitter serotonin?

    This product is the neurotransmitter serotonin.  Other synonyms for this product are 3-(2-Aminoethyl)-5-hydroxyindole hydrochloride, 5-HT, and 5-Hydroxytryptamine hydrochloride.

  7. What are the storage conditions for Product H9523, Serotonin hydrochloride?

    This product is a powder and should be refrigerated at 2-8°C. We do not recommend storing solutions of this product.

  8. Has Product H9523, Serotonin hydrochloride, been cell culture tested?

    No. We do not test this product for cell culture suitability.

  9. What is the purity of Product H9523, Serotonin hydrochloride?

    This product must be at least 98% pure according to our specifications.  The purity for individual lots can be found on the certificate of analysis.

  10. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

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Serotonin (5-hydroxytryptamine, 5-HT) has been linked with several inflammation-associated intestinal diseases, including ulcerative colitis (UC). The largest pool of 5-HT in the body is in enterochromaffin (EC) cells located throughout the intestinal tract. EC cells are mechanosensitive and detect noxious...
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