[The L-DOPA-propranolol test for the evaluation of reserves in secretory growth hormone]

The growth hormone (GH) reserve of 75 short probands (age 1.9 to 23.8 years) was evaluated on the basis of oral L-dopa (300 mg/m2) and propranolol (0.75 mg/kg) administration. The GH response was normal in 21 probands (20.9 +/- 1.24 ng/ml; means +/- SEM) and was found to be higher than the response to the insulin or arginine test. 39 patients failed to respond (less than 6 ng/ml) and were diagnosed as GH deficient. In 15 cases an "intermediate" response (greater than 6 less than 12 ng/ml) was found and in these patients partial GH deficiency was assumed. There was not a single false positive result with this test, which cannot be said for any of the other commonly-used stimulation tests. In two children hypoglycaemic blood glucose levels were observed during the test, whilst in one case loss of consciousness and convulsions were seen. In four patients the test had to be interrupted because of side effects. These children had the following findings in common: GH deficiency was confirmed and the patients were still very young and basal blood glucose levels were relatively low at the beginning of the test. The L-dopa-propranolol test is an effective and reliable GH stimulation test, but severe side effects may occur.