Chemistry - An anabolic steroid, stanozolol occurs as an odorless, nearly colorless, crystalline powder that can exist in two forms: prisms, melting at approximately 235°C, and needles that melt at about 155°C. It is sparingly soluble in alcohol and insoluble in water.
Storage/Stability/Compatibility - Stanozolol tablets should be stored in tight, light-resistant packaging, preferably at room temperature.
Pharmacology - Stanozolol possess the actions of other anabolic agents. It may be less androgenic than other anabolics that are routinely used in veterinary medicine, however. Refer to the discussion in the Boldenone monograph for more information.
Uses/Indications - Labeled indications for the stanozolol product Winstrol®-V (Winthrop/Upjohn) include “... to improve appetite, promote weight gain, and increase strength and vitality...” in dogs, cats and horses. The manufacturer also states that “Anabolic therapy is intended primarily as an adjunct to other specific and supportive therapy, including nutritional therapy.”
Like nandrolone, stanozolol has been used to treat anemia of chronic disease. Because stanozolol has been demonstrated to enhance fibrinolysis after parenteral injection, it may be efficacious in the treatment of feline aortic thromboembolism or in the treatment of thrombosis in nephrotic syndrome. However, at present, clinical studies and/or experience are apparently lacking for this indication.
Pharmacokinetics - No specific information was located for this agent. It is generally recommended that the injectable suspension be dosed on a weekly basis in both small animals and horses.
Contraindications/Precautions - Stanozolol is contraindicated in pregnant animals and in breeding stallions and should not be administered to horses intended for food purposes.
The manufacturer recommends using stanozolol cautiously in patients with cardiac and renal function and with enhanced fluid and electrolyte monitoring.
In humans, anabolic agents are also contraindicated in patients with hepatic dysfunction, hypercalcemia, patients with a history of myocardial infarction (can cause hypercholesterolemia), pituitary insufficiency, prostate carcinoma, in selected patients with breast carcinoma, benign prostatic hypertrophy and during the nephrotic stage of nephritis.
The anabolic agents are category X (risk of use outweighs any possible benefit) agents for use in pregnancy and are contraindicated because of possible fetal masculinization.
Adverse Effects/Warnings - The manufacturer (Winthrop/Upjohn) lists as adverse effects in dogs, cats and horses only “mild androgenic effects” and then only when used with excessively high doses for a prolonged period of time.
Potentially (from human data), adverse reactions of the anabolic agents in dogs and cats could include: sodium, calcium, potassium, water, chloride, and phosphate retention; hepatotoxicity, behavioral (androgenic) changes and reproductive abnormalities (oligospermia, estrus suppression).
Overdosage - No information was located for this specific agent. In humans, sodium and water retention can occur after overdosage of anabolic steroids. It is suggested to treat supportively and monitor liver function should an inadvertent overdose be administered.
Drug Interactions - Anabolic agents as a class may potentiate the effects of anticoagulants. Monitoring of PT’s and dosage adjustment, if necessary of the anticoagulant are recommended.
Diabetic patients receiving insulin may need dosage adjustments if anabolic therapy is added or discontinued. Anabolics may decrease blood glucose and decrease insulin requirements.
Anabolics may enhance the edema that can be associated with ACTH or adrenal steroid therapy.
Drug/Laboratory Interactions - Concentrations of protein bound iodine (PBI) can be decreased in patients receiving androgen/anabolic therapy, but the clinical significance of this is probably not important. Androgen/anabolic agents can decrease amounts of thyroxine-binding globulin and decrease total T4 concentrations and increase resin uptake of T3 and T4. Free thyroid hormones are unaltered and, clinically, there is no evidence of dysfunction.
Both creatinine and creatine excretion can be decreased by anabolic steroids. Anabolic steroids can increase the urinary excretion of 17-ketosteroids. Androgenic/anabolic steroids may alter blood glucose levels. Androgenic/anabolic steroids may suppress clotting factors II, V, VII, and X. Anabolic agents can affect liver function tests (BSP retention, SGOT, SGPT, bilirubin, and alkaline phosphatase).
As an anabolic agent per labeled indications:
a) 0.55 mg/kg (25 mg per 100 pounds of body weight) IM deeply. May repeat weekly for up to and including 4 weeks. (Package Insert; Winstrol®-V —Winthrop/Upjohn)
Monitoring Parameters - 1) Androgenic side effects; 2) Fluid and electrolyte status, if indicated; 3) Liver function tests if indicated; 4) RBC count, indices, if indicated; 5) Weight, appetite
Client Information - Tablets may be crushed and administered with food. Because of the potential for abuse of anabolic steroids by humans, many states have included, or are considering including this agent as a controlled drug. It should be kept in a secure area and out of the reach of children.
Dosage Forms/Preparations/FDA Approval Status/Withholding Times -
Stanozolol Suspension for Injection 50 mg/ml in 10 ml and 30 ml vials; Winstrol®-V (Upjohn); (Rx) Approved for cats, dogs and horses.
Stanozolol Oral Tablets 2 mg; Oral Chewable Tablets 2 mg (dogs only); Winstrol®-V (Upjohn); (Rx) Approved for cats, dogs and horses. In horses, the manufacturer recommends using the injectable product only.
Stanozolol Oral Tablets 2 mg; Winstrol® (Winthrop); (Rx)
Note: All stanozolol products are now controlled drugs (C-IV) in the USA.
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