[Effects of nifuroxazide on fecal flora in healthy subjects]. / Effets du nifuroxazide sur la coproflore du sujet sain.

Effect of nifuroxazide on fecal flora was studied in 12 healthy volunteers receiving, in hazardous order and double-blind procedure, three six-days courses of treatment separated by eight-days spaces of time: the conventional dosage of 400 mg twice a day, a dosage of 1200 mg once a day, and placebo. Among six settled bacteriological index (wealth of the fecal flora, percentage of gram-negative bacteria, numbers of E. coli, Enterococcus, Clostridium and Bacteroides), no significant variation was found by means of statistical study between D0, D2 and D7, nor between the three courses of treatment. Therefore nifuroxazide, even in high dosage, does not injure integrity of microbial intestinal ecosystem under so defined experimental conditions, similar with clinical conditions.

Pharmacokinetic and pharmacodynamic interactions between nifedipine and propranolol or betaxolol.

Pharmacokinetic and pharmacodynamic interactions between nifedipine and two beta-blocking agents were investigated. Eighty mg propranolol twice daily, and 20 mg betaxolol once daily, were randomly administered orally to six young healthy male volunteers, either singly for four days, or combined with nifedipine for the two subsequent days. Nifedipine had similar effects on the pharmacodynamics of both drugs. Nifedipine significantly enhanced propranolol bioavailability and Cmax, but reduced its tmax, in three out of six subjects who were also good absorbers of beta-blockers when taken alone. These effects might be due to enhanced intestinal absorption and/or enhanced first-pass effect, induced by nifedipine.

Effect of diltiazem on plasma glucose, insulin and glucagon during an oral glucose tolerance test in healthy volunteers.

The effect of the calcium antagonist, diltiazem, on glycoregulation was investigated in 12 healthy volunteers using a standard glucose tolerance test. No significant change was observed in plasma glucose, insulin or glucagon levels after oral treatment for B days with diltiazem 180 mg/day.

Pharmacokinetics and metabolism of diltiazem in man.

Dilitazem, a coronary vasodilating agent, after oral administration of four different doses, was well and rapidly absorbed. The pharmacokinetics of the drug followed a two-compartment model, with a rapid distribution and an elimination with a half-life of 4-7 hours. After chronic treatment the pharmacokinetic parameters were practically unchanged and therefore no accumulation of the drug was observed. The comparison between capsule and tablet preparations showed that both forms had a similar bioavailability. Diltiazem was extensively metabilized and only a few percent of the drug was found in urine. Several metabolites, also present as conjugates, have been identified by means of gas chromatography-mass spectrometry.

Pharmacokinetics of the new beta-adrenoceptor blocking agent betaxolol (SL 75212) in man after repeated oral administration.

(+/-)-1-(Isopropylamino)-3-[p-(2-cyclopropyl-methoxyethyl)-phenoxy]-2-propanol HCl (betaxolol, SL 75212) was given to groups of healthy volunteers, 10 mg daily for 7 days followed by 20 mg daily 7 days in one group, and increasing daily doses up to 60 mg/day for a total of 15 days in the other group. The pharmacokinetics were studied during dosing and in the washout period. The pharmacokinetic characteristics were unchanged after repeated doses, T/2 16-22 h, Vd 7.7-8.8 l/kg; clearance 0.28-0.33 l/h/kg.