Biomedical subjects

D S Reeves

Publications and source records attributed to D S Reeves.

At least 199 records · Page 11Linked to original sources

PubMed1979

The pharmacokinetics of trimethoprim and trimethoprim/sulphonamide combinations, including penetration into body tissues.

In this review the pharmacokinetic properties of trimethoprim (TMP) and TMP/sulphonamide combinations are discussed. The concentration of both substances in the various body fluids and tissues differ considerably from the concentrations in blood due to the different distribution of TMP and sulphonamides in the body. As a rule the ratio of the concentration of TMP to sulphonamide is higher in most body fluids and secretions than in blood. If inflammation is present, the concentrations vary considerably. The pharmacokinetic data must be taken into account when making in vitro tests. At the site of inflammation a TMP/sulphonamide concentration factor of 1:0.5 to 1:4 can be expected in urine and of 1:2 to 1:5 in tissue.

Body Fluids↗

PubMed1979

Bactericidal or bacteristatic effects of two sulphonamide plus trimethoprim preparations in human urine.

Rrine collections were made by ten volunteers taking cotrimoxazole and a sulphamoxole/trimethoprim combination on a cross-over basis. The latter was given in approximately half the dose of cotrimoxazole. Following collection of urine and its sterile filtration, the trimethoprim and sulphonamide concentrations were estimated. The urines were then inoculated with various species of Enterobacteriaceae whose minimum inhibitory concentrations had been previously determined. The viable counts in these urines were followed for 24 hours and from these the times to kill 90% of bacteria were calculated. These were very reproducible for any one experiment but showed no correlation with drug concentration, source of the urine or organism sensitivity, except for one organism which had high resistance to both sulphonamide and trimethoprim. When the organism was sensitive to at least trimethoprim a slow bactericidal effect was generally seen with either combination. We concluded that in this type of experiment the higher dosed combination showed no advantage contrary to a previous report, but in agreement with another. This brings into question the current dosage regime of cotrimoxazole when used to treat urinary tract infections in that its higher dosage over certain other sulphonamide/trimethoprim combinations appears to confer no advantage in our experiments.

Bacteriuria↗

PubMed1979

The aminopenicillins: development and comparative properties.

In this review we have compared and contrasted the antibacterial and pharmacological properties of the aminopenicillins currently available. It is apparent that there is little hard evidence (except in the case of thphoid fever) that either amoxycillin or the pro-drug esters of ampicillin are significantly more effective than ampicillin itself, despite their better absorption and higher serum levels. However, amoxycillin and the ampicillin pro-drug esters do cause fewer bowel side-effects than ampicillin, which may justify their use despite the extra cost involved. The problem of susceptibility to penicillinases is unlikely to be solved by modification of the aminopenicillin molecule. A more likely solution is administration of these substances with beta-lactamase inhibitors such as clavulanic acid. Trials with such combinations are already under way.

Amoxicillin↗

PubMed1979