At the age/breed it sounds like your dog has osteoarthritis issues. I would take him to the vet so they can prescribe him pain meds amongst other things (blood test, radiographs) to see that everyhtin is ok. In my opinion pain management is key here. If your dog is happy his quaility of life, healing and overall well being will significantly improve.
As far as those drugs are concerened here are the resources:
Nandrolone
Injectable anabolic steroid; may be useful to stimulate erythropoiesis or to stimulate appetite
Contraindications: hepatic dysfunction, hypercalcemia, history of myocardial infarction, pituitary insufficiency, prostate carcinoma, mammary carcinoma, benign prostatic hypertrophy and during the nephrotic stage of nephritis
Adverse Effects: sodium, calcium, potassium, water, chloride and phosphate retention; hepatotoxicity, behavioral (androgenic) changes and reproductive abnormalities (oligospermia, estrus suppression)
Known teratogen
Pharmacology
Nandrolone exhibits similar actions as other anabolic agents. In the presence of adequate protein and calories, anabolic steroids promote body tissue building processes and can reverse catabolism. As these agents are either derived from or are closely related to testosterone, the anabolics have varying degrees of androgenic effects. Endogenous testosterone release may be suppressed by inhibiting luteinizing hormone (LH). Large doses can impede spermatogenesis by negative feedback inhibition of FSH.
Anabolic steroids can also stimulate erythropoiesis. The mechanism for this effect may occur by stimulating erythropoietic stimulating factor. Anabolics can cause nitrogen, sodium, potassium and phosphorus retention and decrease the urinary excretion of calcium. Many veterinary and human clinicians feel that nandrolone is clinically superior to other anabolics in its ability to stimulate erythropoiesis. It is believed that nandrolone may enhance red cell counts by directly stimulating red cell precursors in the bone marrow, increasing red cell 2,3-diphosphoglycerate and increasing erythropoietin production in the kidney.
Uses/Indications
The principle use of nandrolone in veterinary medicine has been to stimulate erythropoiesis in patients with certain anemias (e.g., secondary to renal failure, aplastic anemias). It has also been suggested for use as an appetite stimulant.
Contraindications/Precautions
No specific recommendations were located for this agent in veterinary species.
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).
Doses
Dogs
For treatment of anemia in patients with chronic renal failure:
1. 1-1.5 mg/kg IM once weekly; may require 2-3 months to achieve beneficial effects (Polzin and Osborne 1985)
2. 5 mg/kg IM (maximum of 200 mg/week) every 2-3 weeks (Ross et al. 1988)
For treatment of metabolic and endocrine anemias:
1. 5 mg/kg IM once weekly (maximum of 200 mg); most resolve with correction of underlying disease process (Maggio-Price 1988)
For aplastic anemia:
1. 1-3 mg/kg IM weekly (Weiss 1986)
As an appetite stimulant:
1. 5 mg/kg IM (max. 200 mg/week) weekly (Macy and Ralston 1989)
Testosterone Cypionate | Testosterone Enanthate | Testosterone Propionate
Prescriber Highlights
Principle endogenous androgen used primarily for the treatment of testosterone-responsive urinary incontinence in neutered male dogs/cats; in bovine medicine to produce an estrus-detector animal
Contraindications: known hypersensitivity to the drug; prostate carcinoma. Caution: renal, cardiac or hepatic dysfunction
Adverse Effects: Uncommon, but perianal adenomas, perineal hernias, prostatic disorders and behavior changes possible
Pharmacology
The principle endogenous androgenic steroid, testosterone is responsible for many secondary sex characteristic of the male as well as the maturation and growth of the male reproductive organs and increasing libido.
Testosterone has anabolic activity with resultant increased protein anabolism and decreased protein catabolism. Testosterone causes nitrogen, sodium, potassium and phosphorus retention and decreases the urinary excretion of calcium. Nitrogen balance is improved only when an adequate intake of both calories and protein occurs.
By stimulating erythropoietic stimulating factor, testosterone can stimulate the production of red blood cells. Large doses of exogenous testosterone can inhibit spermatogenesis through a negative feedback mechanism inhibiting luteinizing hormone (LH).
Testosterone may help maintain the normal urethral muscle tone and the integrity of the urethral mucosa in male dogs. It may also be necessary to prevent some types of dermatoses.
Uses/Indications
The use of injectable esters of testosterone in veterinary medicine is limited primarily to its use in dogs (and perhaps cats) for the treatment of testosterone-responsive urinary incontinence in neutered males. Testosterone has been used to treat a rare form of dermatitis (exhibited by bilateral alopecia) in neutered male dogs. These drugs are also used in bovine medicine to produce an estrus-detector (teaser) animal in cull cows, heifers, and steers.
The use of testosterone to increase libido, treat hypogonadism, aspermia and infertility in domestic animals has been disappointing.
Testosterone is metabolized in the liver and is, with its metabolites, excreted in the urine (90%) and the feces (6%). The plasma half-life of testosterone has been reported to be between 10-100 minutes in humans. The plasma half-life of testosterone cypionate has been reported to be 8 days.
Contraindications/Precautions
Testosterone therapy is contraindicated in patients with known hypersensitivity to the drug or prostate carcinoma. It should be used with caution in patients with renal, cardiac or hepatic dysfunction.
Adverse Effects/Warnings
Adverse effects are reportedly uncommon when injectable testosterone products are used in male dogs to treat hormone-responsive incontinence. Perianal adenomas, perineal hernias, prostatic disorders and behavior changes are all possible, however. Behavioral changes have been reported in cats. Polycythemia has been reported in humans receiving high dosages of testosterone. High dosages or chronic usage may result in oligospermia or infertility in intact males.
Drug Interactions
Testosterone administered with oral anticoagulants may cause increased bleeding in some patients. Diligent monitoring is necessary if patients are receiving androgens and oral anticoagulants. Anticoagulant dosage adjustments may be necessary when adding or discontinuing androgen therapy.
Diabetic patients receiving insulin may need dosage adjustments if androgen therapy is added or discontinued. Androgens may decrease blood glucose and decrease insulin requirements.
Androgens 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 testosterone therapy, but the clinical significance of this is probably not important. Androgen agents can decrease amounts of thyroxine-binding globulin and decrease total T4concentrations 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 testosterone. Testosterone 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.
Doses
Dogs
For testosterone-responsive urinary incontinence (may be used with phenylpropanolamine):
1. Testosterone propionate: approximately 2 mg/kg IM or SC 3 times per week. Testosterone cypionate: 200 mg IM once per month (LaBato 1988), (Polzin and Osborne 1985)
2. Testosterone propionate: 2.2 mg/kg IM q2-3 days. Testosterone cypionate: 2.2 mg/kg IM once per month (Moreau and Lappin 1989), (Chew, DiBartola, and Fenner 1986)
3. Testosterone cypionate: 2.2 mg/kg IM q4-8 weeks (Lane 2002b)
For estrus control: Testosterone enanthate or cypionate 0.5 mg/kg IM once every 5 days or methyltestosterone tablets 25 mg PO twice a week (Note this dose is for Greyhound-sized dogs) (Purswell 1999)
To reduce mammary gland enlargement seen in pseudopregnancy: Testosterone enanthate or cypionate 0.5-1 mg/kg IM once (Purswell 1999)
Anyway hope this helps... Cosequin is great as well