Product Overview
- Product Name: Promethazine
- Active Form: Promethazine Hydrochloride
- CAS Number: 58-33-3
- Molecular Formula: C17H20N2S·HCl
- Molecular Weight: 320.88
- Drug Class: First-generation phenothiazine-class H1-receptor antagonist (antihistamine)
Note: Promethazine free base is generally not used as a pharmaceutical raw material; the active pharmaceutical ingredient (API) registered in the pharmaceutical market and used for formulation production is promethazine hydrochloride.
What is Promethazine?
Promethazine—commonly used in the form of Promethazine Hydrochloride—is a phenothiazine-class antihistamine API. Our pharmaceutical-grade Promethazine Hydrochloride API is characterized by high purity and low impurity levels, making it suitable for the production of various pharmaceutical formulations.
In addition to being used in single-ingredient formulations, Promethazine Hydrochloride can be combined with other active ingredients; for example, it is combined with Dextromethorphan Hydrobromide to produce Promethazine DM, and with Codeine to produce Promethazine Codeine.
Why choose Highassay?
We are a professional Chinese supplier of Promethazine Hydrochloride API, offering high-purity (≥99%) Promethazine Hydrochloride powder.
- Documentation Support：Batch COA, MSDS/SDS available
- Quality Control：Meet USP / EP / BP / CP Standards
- Delivery Stability：Stable production capacity & batch traceability
Sales & Logistics Information
Packaging Services
Standard packaging: 25kg/drum (fiber drum with double-layer PE inner liners).
Customized packaging: Packaging can be tailored to your specific requirements to facilitate production and storage.
Sample Services
We offer free samples; please click the contact link on the right to request one if needed.
Delivery Commitment
Small orders: In-stock items available for shipment within 1–3 days.
Large orders: Shipment arranged within 7–15 days.
Shipping Services
The product is securely packaged and suitable for air or sea transport.
Storage Recommendations
Store in a cool, dry, and well-ventilated area; keep the packaging tightly sealed.
Note: As this product is a pharmaceutical raw material, we will provide the necessary shipping documentation and relevant technical data.
Specification of Promethazine HCL
- Specification of Promethazine HCL
| Test Item | Specification |
|---|---|
| Appearance | White or almost white crystalline powder |
| Solubility | Freely soluble in water, soluble in ethanol and chloroform; practically insoluble in ether |
| Melting Point | About 230°C (with decomposition upon melting) |
| Identification | UV spectrum, IR spectrum and chloride reaction show positive results |
| Clarity and Color of Solution | The solution is clear and colorless; if colored, it shall not be deeper than the yellow standard color comparison solution |
| pH Value | 4.0 ~ 5.0 (1% aqueous solution) |
| Assay (on dried basis) | 99.0% ~ 101.0% |
| Related Substances | Any individual impurity ≤ 0.5%, Total impurities ≤ 2.0% |
| Loss on Drying | ≤ 0.5% |
| Residue on Ignition | ≤ 0.1% |
| Heavy Metals | ≤ 20 ppm |
| Residual Solvents | Complies with ICH Q3C limits |
Yes; it is frequently used in the development of formulations for dry coughs and coughs caused by allergic irritation.
Promethazine DM is the name of a finished pharmaceutical product containing promethazine and dextromethorphan as its primary active ingredients; it effectively relieves symptoms such as dry, non-productive coughs, runny noses, and itchy eyes. It is primarily available in the form of Promethazine DM syrup.
Phenergan is the brand name for Promethazine Hydrochloride, while Promethazine is its active pharmaceutical ingredient.
Phenergan can be used to alleviate nausea and vomiting.
No; although both are ready-to-use bottled syrups, they have different formulations and indications. Furthermore, Promethazine DM is a prescription medication, whereas Robitussin DM is an over-the-counter product.
Promethazine Hydrochloride (as a single-ingredient product) is not a controlled substance, whereas compound preparations containing codeine are controlled substances.
What is Promethazine Used For?
The Promethazine Hydrochloride API we supply is primarily used in four types of finished dosage forms: tablets, oral solutions/syrups, injections, and suppositories. It demonstrates significant efficacy in providing sedation, preventing vomiting, and treating motion sickness.
The specific dosage form does not affect the drug’s inherent pharmacological action; differences lie solely in the route of administration and the clinical setting in which it is used.
Promethazine tablets/pills
- Common dosages: 12.5 mg, 25 mg, 50 mg (often appearing as a white, round pill marked “k3”).
- Tablets have a relatively slow onset of action and are suitable for manageable symptoms that do not require rapid intervention.
Promethazine oral solution/syrup
- Common dosage: 6.25 mg/5 mL; compatible with sugar-free cough syrup formulations.
- Suitable for children or patients who have difficulty swallowing tablets.
Promethazine injection
- Commonly used as an alternative when the oral route is not feasible or is contraindicated.
Promethazine suppository
- Route of administration: Rectal.
Important Safety Warning: Use is strictly prohibited in children under 2 years of age, regardless of the dosage form, due to a definite risk of fatal respiratory depression.
Promethazine Free Base vs. Promethazine Hydrochloride
- Promethazine free base: Its molecular formula is C₁₇H₂₀N₂S, and its molecular weight is approximately 284.42. Although it is the active pharmaceutical ingredient, it is poorly soluble in water on its own and is therefore rarely used directly in formulations.
- Promethazine hydrochloride: Its molecular formula is C₁₇H₂₀N₂S·HCl, and its molecular weight is approximately 320.88. When promethazine free base combines with a molecule of hydrochloric acid, its solubility increases significantly; it becomes highly soluble in water, making it suitable for the preparation of dosage forms such as injections or oral solutions.
Highassay offers a pharmaceutical-grade Promethazine Hydrochloride API with excellent water solubility; our product meets formulation requirements while retaining the full pharmacological effects of the free base (such as antihistamine, sedative, and antiemetic properties).
| Comparison Item | Promethazine Base | Promethazine Hydrochloride |
|---|---|---|
| Chemical Nature | Active pharmaceutical ingredient (free base) | Salt formed by free base combined with hydrochloric acid |
| Molecular Formula | C₁₇H₂₀N₂S | C₁₇H₂₀N₂S·HCl |
| Molecular Weight | Approx. 284.42 | Approx. 320.88 |
| Water Solubility | Sparingly soluble in water | Freely soluble in water |
| Formulation Application | Generally not used directly in pharmaceutical formulations | The form applied clinically (tablets, injections, etc.) |
| Pharmacological Action | Antihistamine, sedative, antiemetic, etc. | Identical to promethazine base |
