MAST P 150

Drostanolone Propionate Injection

Product Name & Packaging
Brand Name: MAST P 150
Generic Name: Drostanolone propionate (also referred to as dromostanolone propionate)
Strength & Packaging: 10 mL multidose vial | 150 mg/mL. The active ingredient is the propionate ester of drostanolone, a synthetic androgen/anabolic steroid.

Description

MAST P 150 is an oil-based injectable preparation containing drostanolone propionate. Pharmacopeial monograph text describes drostanolone propionate injection as an oily solution for injection and as a clear, colorless to pale yellow, oily liquid. Pharmacology references describe drostanolone as a synthetic androgen with properties similar to testosterone.

Indications

For medical-reference wording, drostanolone propionate has been described as an androgenic, anabolic steroid used as an antineoplastic agent in the palliative treatment of advanced metastatic, inoperable breast cancer in certain postmenopausal women, administered intramuscularly. At the same time, the Guide to Pharmacology notes that alternative treatments are generally used and that this drug does not appear to be approved for use by the U.S. FDA or the European Medicines Agency.

Dosage & Administration

Route: Intramuscular injection.
Because this 150 mg/mL brand-specific presentation is not a standard modern reference product with broadly accepted current prescribing guidance, a fixed catalog dosage should not be stated. A safe professional entry is:

“Administer only under the direction of a licensed healthcare professional and in accordance with the manufacturer’s labeling, local regulations, and clinical judgment.”

This keeps the listing medically appropriate while aligning with the reference description that drostanolone propionate is administered intramuscularly.

Mechanism of Action

Drostanolone propionate acts through androgen receptor signaling. Reference sources describe drostanolone/dromostanolone as a synthetic androgen, and PubChem notes that dromostanolone binds to androgen receptors, leading to downstream genetic transcriptional effects.

Precautions

Use requires careful professional oversight because clinical-use references note a high risk of virilization, especially in women. The Guide to Pharmacology also indicates that drostanolone propionate is no longer a routinely favored treatment option, with alternative therapies generally preferred.

Side Effects

Potential adverse effects include virilization/masculinization-related effects, such as acne, increased hair growth, and voice changes. The clinical summary specifically highlights a high risk of virilization with therapeutic use.

Storage

Store in a tight, light-resistant container. Pharmacopeial monograph text for drostanolone propionate injection specifies tight containers and light-resistant storage.