Why flucloxacillin before food

This is because enzymes in the intestines break down many types of medicines such as macrolide antibiotics and chemicals in grapefruit block these enzymes and disrupt their function. Because the breakdown enzymes are not functioning properly, the antibiotics stay in your body for longer and the level in your bloodstream may become too high. This increases your chance of experiencing side effects from the medication.

Eating grapefruit or drinking grapefruit juice can affect antibiotic metabolism for up to 72 hours. Although the information above highlight which antibiotics should be taken before or after food, we recommend consulting your pharmacist if you have any queries about when to take your medication.

If you regularly take repeat medication, you may wish to consider using services such as RXLive , which provide a free delivery service to ensure you never miss your medication again and have a dedicated pharmacist ready to chat at all times. Serrated line: fed; continuous line: fasting. Relevant MIC 90 of S. Also shown is the MIC 50 of S. This study in volunteers investigated the impact of a standardized, high-fat, high-calorie meal on free flucloxacillin pharmacokinetics, using a sensitive assay, over the full concentration-time curve and with regard to contemporary pharmacodynamic targets.

Flucloxacillin taken with food was associated with a significant reduction in free and total AUC and C max , and a prolonged T max , as shown with total flucloxacillin concentrations in previous studies [ 5 , 6 ]. These effects resulted from a decrease in oral availability, a longer T lag and a lower k a.

Differences in achievement of pharmacodynamic targets were minor and ranged from a small reduction in PTA for a free concentration target of greater than 0. These results have important implications for clinical practice as they provide a scientific basis for reconsidering the recommendation that flucloxacillin should always be administered on an empty stomach.

For this patient group, bacteriostasis is probably all that is necessary. For the small subpopulation of patients infected with a strain of S. It is often difficult to determine whether skin and soft tissue infections such as cellulitis are caused by S.

In either case the MIC of the pathogen is rarely known, so that the most certain approach in these conditions may be to recommend administration on an empty stomach. Nevertheless, this potential gain in a small proportion of cases must be balanced against the difficulty that many patients experience in remembering to take flucloxacillin an hour before meals and the likelihood of missed doses, which may have a much greater effect on the clinical efficacy.

Additionally, if it was clinically important to reach a bactericidal target for all potentially infecting S. In these situations, oral flucloxacillin in doses of mg 6-hourly, irrespective of whether it is taken with food or in the fasting state, may fail to achieve adequate therapeutic targets for many strains and an alternative treatment strategy should be considered.

An increase in the oral flucloxacillin dose beyond mg or dosing frequency e. This supports results from other volunteer studies [ 23 ]. The results were modelled for both 6- and 8-hourly dosing, as both regimens have been recommended, and because in practice it is almost impossible to dose precisely every 6 hours. At the least it is likely that there will be an 8-hour delay while the patient sleeps. There are several limitations to this study.

It was conducted with a fixed dose of mg of flucloxacillin in young, healthy volunteers with a relatively normal BMI and normal renal function. In practice, flucloxacillin is administered to patients with a wide range of age, BMI, and renal function [ 24 — 26 ].

Patients with impaired clearance of flucloxacillin will have an increase in the PTA, both with and without food, and this may increase the chance of therapeutic success. Additionally, the food given to the volunteers was a high-fat, high-calorie meal, and this may be larger than that usually consumed by patients. Any effect of administration with meals in clinical practice may well be less than demonstrated here with volunteers.

We have not investigated the effect of food on doses of flucloxacillin other than mg, but it is likely that the effect would be similar. Finally, the steady-state data rests on the validity of the one compartment model with T lag and first-order absorption.

Because of the uncertainty of translating these findings into clinical practice it would be useful to study pharmacodynamic target attainment of flucloxacillin concentrations in the variety of clinical settings in which oral flucloxacillin is prescribed. These findings in adults may not translate directly into the paediatric population and this would be worthy of further study given that oral administration of flucloxacillin is particularly difficult in children [ 27 ].

Finally, it should not be assumed that the findings of this study extend to other isoxazolyl penicillins, but this too warrants further investigation.

Contrary to what has been widely accepted since the s, the results of this study indicate that taking flucloxacillin with food may not compromise effective flucloxacillin plasma concentrations in most circumstances. Other potential advantages of taking flucloxacillin with food include convenience, improved compliance and reduction in adverse effects such as nausea. Rather than focusing on administration on an empty stomach, it is more important that dosing is individualized according to known or suspected susceptibility to flucloxacillin, illness severity, and host characteristics.

The findings of this study have significant implications for dosing of oral flucloxacillin worldwide. For comparision with Fig 4 in paper. National Center for Biotechnology Information , U. PLoS One. Published online Jul Sharon J. Philip G. Jared K. Heather L. Richard J.

Stephen T. Evan J. Jacobus P. Author information Article notes Copyright and License information Disclaimer. Competing Interests: The authors have declared that no competing interests exist. Received Feb 16; Accepted Apr This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article has been cited by other articles in PMC. Associated Data Supplementary Materials S1 Dataset: Raw flucloxacillin urine concentration results fed versus fasting. It'll help stop the infection coming back. Tell your doctor if you don't start feeling better after taking flucloxacillin for 3 days. Also tell them if, at any time, you start to feel worse.

Some people get a fungal infection called thrush after taking a course of antibiotics like flucloxacillin. It happens because antibiotics kill the normal harmless bacteria that help to protect you against thrush. Flucloxacillin doesn't stop contraceptive pills working, including the combined pill or emergency contraception.

However, if flucloxacillin makes you vomit or have severe diarrhoea 6 to 8 watery poos in 24 hours for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Look on the pill packet to find out what to do.

Read more about what to do if you're on the pill and you're being sick or have diarrhoea. There's no firm evidence to suggest that taking flucloxacillin will reduce fertility in either men or women.

Yes, flucloxacillin shouldn't affect you being able to drive or cycle. You don't need to avoid any foods or drinks while taking flucloxacillin. However, make sure to take it on an empty stomach. Page last reviewed: 23 November Next review due: 23 November Flucloxacillin On this page About flucloxacillin Key facts Who can and can't take flucloxacillin How and when to take it Side effects How to cope with side effects Pregnancy and breastfeeding Cautions with other medicines Common questions.

About flucloxacillin Flucloxacillin is an antibiotic. Help us improve our website Can you answer a quick question about your visit today? Take flucloxacillin on an empty stomach. For most infections, you should feel better within a few days. The most common side effects are feeling sick nausea and diarrhoea. You can drink alcohol while taking flucloxacillin. Flucloxacillin is called by the brand name Floxapen.

Flucloxacillin can be taken by children. To make sure flucloxacillin is safe for you, tell your doctor if you: have had an allergic reaction to penicillin, flucloxacillin or any other medicines in the past have liver or kidney problems have recently had, or are about to have, any vaccinations. Important Carry on taking this medicine until you've completed the course, even if you feel better. How to take it Swallow flucloxacillin capsules whole with a drink of water.

What if I forget to take it? Always take your flucloxacillin exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions. How to take flucloxacillin Flucloxacillin is best taken on an empty stomach, one hour before eating food. Capsules : swallow the capsule with a glass of water. Do not chew them. Liquid : shake the medicine well. Measure the right amount using an oral syringe or medicine spoon.

You can get these from your pharmacy. Do not use a kitchen spoon as it will not give you the right amount. Read more: Tips on how to give medicines to babies and children. Timing: Take flucloxacillin at the same times each day.

Try to space your doses evenly throughout the day. Three times each day: this should be in the morning, early afternoon and at bedtime. Four times each day: this should be about 4 hours apart, for example 7am, 11am, 3pm and 7pm. Missed dose: If you forget to take your dose at the correct time, take one as soon as you remember.

Try to take the correct number of doses each day. Do not take two doses at the same time to make up for a forgotten dose.