R-Gene 10

Each 100 mL of R-Gene® 10 (10% Arginine Hydrochloride Injection, USP) for intravenous use contains 10 g of L-Arginine Hydrochloride, USP in Water for Injection, USP. L-arginine is a naturally occurring amino acid.
R-Gene 10 is hypertonic (950 mOsmol/liter) and contains 47.5 mEq of chloride ion per 100 mL of solution. The pH is adjusted to 5.6 (5.0–6.5) with arginine base or hydrochloric acid.
Intravenous infusion of R-Gene 10 often induces a pronounced rise in the plasma level of human growth hormone (HGH) in subjects with intact pituitary function. This rise is usually diminished or absent in patients with impairment of this function
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 (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 highly allergic tendencies.
There have been two reports of possible overdosage of R-Gene 10 in children. 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.
R-Gene 10 should always be administered by intravenous injection because of its hypertonicity.
A suitable antihistaminic drug should be available in the event that an allergic reaction occurs.
R-Gene 10 is a diagnostic aid and is not intended for therapeutic use.
R-Gene 10 is a hypertonic (950 mOsmol/liter) and acidic (average pH of 5.6) solution that can irritate tissues. Care should be used to insure 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 Category B
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.