The effect of sudanese diet on the bioavailability of ampicill1n

Do dietary interventions exert clinically important effects on the bioavailability of β-lactam antibiotics? A systematic review with meta-analyses

BACKGROUND

Managing drug-food interactions may help to achieve the optimal action and safety profile of β-lactam antibiotics.

METHODS

We conducted a systematic review with meta-analyses in adherence to PRISMA guidelines for 32 β-lactams. We included 166 studies assessing the impact of food, beverages, antacids or mineral supplements on the pharmacokinetic (PK) parameters or PK/pharmacodynamic (PK/PD) indices.

RESULTS

Eighteen of 25 β-lactams for which data on food impact were available had clinically important interactions. We observed the highest negative influence of food (AUC or Cmax decreased by >40%) for ampicillin, cefaclor (immediate-release formulations), cefroxadine, cefradine, cloxacillin, oxacillin, penicillin V (liquid formulations and tablets) and sultamicillin, whereas the highest positive influence (AUC or Cmax increased by >45%) for cefditoren pivoxil, cefuroxime and tebipenem pivoxil (extended-release tablets). Significantly lower bioavailability in the presence of antacids or mineral supplements occurred for 4 of 13 analysed β-lactams, with the highest negative impact for cefdinir (with iron salts) and moderate for cefpodoxime proxetil (with antacids). Data on beverage impact were limited to 11 antibiotics. With milk, the extent of absorption was decreased by >40% for cefalexin, cefradine, penicillin G and penicillin V, whereas it was moderately increased for cefuroxime. No significant interaction occurred with cranberry juice for two tested drugs (amoxicillin and cefaclor).

CONCLUSIONS

Factors such as physicochemical features of antibiotics, drug formulation, type of intervention, and patient's health state may influence interactions. Due to the poor actuality and diverse methodology of included studies and unproportionate data availability for individual drugs, we judged the quality of evidence as low.

Effects of oils and pharmaceutical excipients on the bioavailability of ampicillin orally administered, different oily and aqueous suspensions in rabbit

The in vivo bioavailability and in vitro drug-release studies of ampicillin trihydrate in different oily and aqueous suspensions have been investigated. In addition, partition, solubility, and rheological measurements have also been carried out. The in vivo experimental design was based on a 6 x 6 latin square using the rabbit as the test animal. The bioavailability of ampicillin was determined using the plasma levels, which were measured microbiologically. Results of the study showed that oily and sucrose-containing aqueous formulations enhanced the extent of ampicillin absorption, although not statistically significantly, but was close to the borderline of significance. Ampicillin appears to be absorbed at essentially the same rate from both aqueous and oily formulations. The latter showed plasma-level time curves with biphasic absorption and are likely to produce prolonged plasma concentrations of ampicillin because of the effects of enterohepatic recycling. Viscosity appears to play an insignificant role in the results obtained since the bioavailability parameters correlate poorly with the viscosity except Cmax. It is suggested that enhancement in the bioavailability of ampicillin is due to the decrease in the gut transit rate brought about by the oil which predominates and masks the other effects of viscosity and osmotic effects of sucrose. The existence of a correlation between the in vitro drug-release rate (t50%) and viscosity and the lack of a correlation between in vivo and in vitro parameters support the above suggestion and indicate that traditional dissolution rate tests, such as flask-stirrer method, are unsatisfactory as bioavailability indicators when applied to dosage forms that caused marked changes in physiological factors like GER and biliary excretion.

Effect of the interval between feeding and drug administration on oral ampicillin absorption in dogs

Eight dogs of various breeds received single oral doses of 20 mg/kg bodyweight ampicillin at four different time intervals relative to feeding a meal. In treatment A the dogs were fasted for 12 hours before and after ampicillin administration. In treatment B the dogs received ampicillin immediately after, in treatment C one hour before and in treatment D two hours after the meal. Each dog received these treatments during a period of feeding dry and canned dog food according to an 8 x 8 Latin square design. Blood samples were taken at specified time intervals after drug administration by jugular venepuncture. Antibiotic concentrations in plasma were determined by microbiological assay. Non-compartmental pharmacokinetic parameters were calculated from the individual concentration-time curves and were compared by non-parametric statistic tests between treatments and types of food. With both dry and canned food ampicillin absorption was impaired when the drug and food were given at the same time (treatment B) as compared to the absorption in fasting dogs (treatment A and C). On dry food, drug absorption was also decreased in treatment D. It is recommended for clinical purposes to give ampicillin to fasted dogs, and to wait at least one hour before feeding. After a meal (dry food) waiting two hours until drug administration is not sufficient to avoid impaired ampicillin absorption.