Arginine Hydrochloride

R-Gene ® 10 is indicated as an intravenous stimulant to the pituitary for the release of human growth hormone in patients where the measurement of pituitary reserve for HGH can be of diagnostic usefulness. It can be used as a diagnostic aid in such conditions as panhypopituitarism, pituitary dwarfism, chromophobe adenoma, postsurgical craniopharyngioma, hypophysectomy, pituitary trauma, acromegaly, gigantism and problems of growth and stature. If the insulin hypoglycemia test has indicated a deficiency of pituitary reserve for HGH, a test with R-Gene ® 10 is advisable to confirm the negative response. This can be done after a waiting period of one day. As patients may not respond to R-Gene ® 10 (Arginine Hydrochloride Injection, USP) during the first test, the unresponsive patient should be tested again to confirm the negative result. A second test can be performed after a waiting period of one day. Some patients who respond to R-Gene ® 10 do not respond to insulin and vice versa. The rate of false positive responses for R-Gene ® 10 is approximately 32%, and the rate of false negatives is approximately 27%.

The administration of R-Gene ® 10 is contraindicated in persons having known hypersensitivity to any ingredient in this product.

There have been reports of overdosage of R-Gene ® 10 in pediatric patients leading to death. EXTREME CAUTION MUST BE EXERCISED WHEN INFUSING R-GENE ® 10 INTO PEDIATRIC PATIENTS. OVERDOSAGE OF R-GENE ® 10 IN PEDIATRIC PATIENTS CAN RESULT IN HYPERCHLOREMIC METABOLIC ACIDOSIS, CEREBRAL EDEMA, OR POSSIBLY DEATH. Hypersensitivity reactions, including anaphylaxis have been reported. Appropriate medical support should be available during R-Gene ® 10 administration. If anaphylaxis or other serious hypersensitivity reaction occurs, R-Gene ® 10 should be discontinued and appropriate medical treatment initiated. R-Gene ® 10 should always be administered by intravenous infusion because of its hypertonicity. R-Gene ® 10 is a diagnostic aid and is not intended for therapeutic use.

General R-Gene ® 10 is a hypertonic (950 mOsmol/liter) and acidic (average pH of 5.6) solution that can cause irritation and damage to tissues. Care should be used to ensure administration of R-Gene ® 10 through a patent catheter within a patent vein. Excessive rates of infusion may result in local irritation and in flushing, nausea, or vomiting. Inadequate dosing or prolongation of the infusion period may diminish the stimulus to the pituitary and nullify the test. The arginine in R-Gene ® 10 can be metabolized resulting in nitrogen-containing products for excretion. The effect of an acute amino acid or nitrogen burden upon patients with impairment of renal function should be considered when R-Gene ® 10 is to be administered. The chloride content of R-Gene ® 10 is 47.5 mEq per 100 mL of solution, and the effect of infusing this amount of chloride into patients with electrolyte imbalance should be evaluated before the test is undertaken. It should be noted that the basal and post stimulation levels of growth hormone are elevated in patients who are pregnant or are taking oral contraceptives. Carcinogenesis, mutagenesis, and impairment of fertility Long term animal studies have not been performed to evaluate the carcinogenic potential, the mutagenic potential or the effect on fertility of intravenously administered R-Gene ® 10. Pregnancy Reproduction studies have been performed in rabbits and mice at doses 12 times the human dose and have revealed no evidence of impaired fertility or harm to the fetus due to R-Gene ® 10 (10% Arginine Hydrochloride Injection, USP). There have been no adequate or well controlled studies for the use of R-Gene ® 10 in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should not be used during pregnancy. Nursing Mothers It is not known whether intravenous administration of R-Gene ® 10 could result in significant quantities of arginine in breast milk. Systemically administered amino acids are secreted into breast milk in quantities not likely to have a deleterious effect on the infant. Nevertheless, caution should be exercised when R-Gene ® 10 is to be administered to nursing women. Geriatric Use Clinical studies of arginine did not include a sufficient number of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients.

Adverse reactions associated with 1670 infusions in premarketing studies were as follows: Non-specific side effects consisting of nausea, vomiting, headache, flushing, numbness and local venous irritation were reported in approximately 3% of the patients. One patient had an allergic reaction which was manifested as a confluent macular rash with reddening and swelling of the hands and face. The rash subsided rapidly after the infusion was terminated and 50 mg of diphenhydramine were administered. One patient had an apparent decrease in platelet count from 150,000 to 60,000. One patient with a history of acrocyanosis had an exacerbation of this condition following infusion of R-Gene ® 10. Post Marketing Experience: The following adverse events have been reported during post-marketing use: extravasation leading to burn-like reaction and/or skin necrosis requiring surgical intervention, hypersensitivity reactions including anaphylaxis, and hematuria that in some cases occurred 1–2 days after an R-Gene ® 10 administration. Because these adverse events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Reproduction studies have been performed in rabbits and mice at doses 12 times the human dose and have revealed no evidence of impaired fertility or harm to the fetus due to R-Gene ® 10 (10% Arginine Hydrochloride Injection, USP). There have been no adequate or well controlled studies for the use of R-Gene ® 10 in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should not be used during pregnancy.

It is not known whether intravenous administration of R-Gene ® 10 could result in significant quantities of arginine in breast milk. Systemically administered amino acids are secreted into breast milk in quantities not likely to have a deleterious effect on the infant. Nevertheless, caution should be exercised when R-Gene ® 10 is to be administered to nursing women.

Clinical studies of arginine did not include a sufficient number of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients.