1. Asensitiveand specific radioimmunossay (RIA) permitting quantitation of pharmacological levels of digoxin in human plasma has been developed. 2. High titer digoxin specific antibodies were obtained by immunizing rabbits with digoxin coupled by periodate oxidation method to bovine serum albumin. Anti-bodies produced by three animals have been extensively characterized regarding their suitability for RIA. 3. The assay involves use of tritiated digoxinand coated charcoal for separation of free and antibody bound radioactivity; assay is rapid and can readily cope with a large number of plasma samples and is adaptable for assay of digoxin in serum and urine samples. 4. The procedure has been evaluated by measuring plasma levels of digoxinin patients on digitalis therapy. Samples taken 12 hours after the last dose of digoxin showed a range of 0.36 to 3.14 ng/ml, with a mean value of 1.09 ( 0.8 ng/ml; the method is suitable for monitoring digoxin therapy.

1. A clinical trial has been carried out in ten patients with cerebellar ataxia of varying etiology to assess the effectiveness of oral choline chloride and lithium carbonate individually or in combination. 2.The parameters for assessment of improvement included the intensity of tremor, the distance of overshoot from fixed point 'during coordination tests, degree of nystagmus, maximum interpedal distance without ataxia with eyes open, gait and hand-writing charts. 3. The symptoms and signs of cerebellar disease showed partial improvement with administration of choline chloride which were markedly ameliorated by concurrent administration of lithium carbonate.

1. Nitroxazepine (2.6 X IO-8M) produced leftward shift of dose responses curve of noradrenaline (5.9 X IO-7 M to 1.7 X 10-4M) and also produced time dependent potentiation to noradrenaline (5.9 X IO-7 M) threshold response. 2. Nialamide (1.6 X l0-5 M) pyrogallol (2.3 X IO-5M) and desipmmine (1.8 X 10-5 M) produced potentiation of the threshold responses to noradrenaline. In the presence of nialamide and pyrogallol, nitroxazepine further potentiated the responses to noradrenaline. However in the presence of desipramine, no further potentiation by nitoxazepine was observed. 3. The responses to methoxamine (4.0 X l0-7 to 1.2 X I0-5M) were not affected by nitroxazepine. A sympathomimetic effect of nitroxazepine involving inhibition of noradrenaline uptake is suggested on the basis of data obtained.

1 Different pharmacokinetic parameters of dapsone were studied, following oral administration of dapsone (100 mg.) alone or in combination with dipyrone(1000 mg.) in six untreated patients of leprosy, over a period of 8 hours. 2. The mean blood levels, the mean serum half-life and the mean AUC O-8 hrs of dapsone were reduced in the presence of dipyrone. 3. The cumulative urinary excretion of dapsone was increased following the administration of dapsone and dipyrone in combination.

I. Plasma concentrations of pencillin G (10,000 iu/kg.) and Ampicillin (6 mg/kg.) (administered intramuscularly) in six buffalo calves were estimated at different time intervals by microbiological.assay. 2. Penicillin G attained a peak concentration of 9.53 ( 1.46 iu/ml. at 15 min. and the therapeutic concentration (Cpther) was maintained for about 5 hr. -3. 3.On the other hand, ampicillin attained its peak concentration of 8.50 ( 1.28 (g/ml at 1 hr and its Cpther, was maintained for about 8 hr. 4. The elimination half-life( t1/2 B) was found to be 1.10 ( 0.20 hr and 1.35 ( 0.32 hr for penicillin G and ampicillin respectively.

1. Morphine and pentazocine two commonly used pre-anaesthetic medicants were used singly as well as in combinations with anticholinergics (atropine or hyoscine) and in triple combinations with the addition of diazepam for their effects on the safety index of ether and halothane in mice. 2.Safety index (SI) of ether as well as halothane was significantly raised by triple combinations containing morphine/pentazocine + diazepam + atropine/hyoscine. In double,combinations, morphine in combination with diazepam markedly raised the SI of both the anaesthetics.

S 1. Tolmetin (10 mg/kg) per se produced hypoglycaemia. 2. On concurrent administration, tolmetin potentiated the glybenclamide induced hypoglycaetnia. 3. It is postulated that the tolmetin hypoglycaemia may be mediated byprostaglandins.