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A type of penicillin, Flucloxacillin is an antibiotic that is used to treat infections, mainly skin, chest, or bone infections. It is suitable for kids and pregnant women too. In this article, we have considered what Flucloxacillin is, and what we need to know about its use. The amount of frequency and duration of doses is advised by a doctor. Although it is a medicine safe for kids, it can sometimes have side effects with one needs to look out for. Some of these side effects are relatively more common and less dangerous, but the other extreme and rare side effects are harmful and require immediate medical assistance.

We have looked at these side effects along with any signs of an allergic reaction as well. One must always ensure that he/she is not allergic to Penicillin before consuming flucloxacillin. Doctors advise against consuming alcohol when using certain antibiotics. Fortunately, flucloxacillin is considered to be safe and there are no immediate or direct dangers involved. However, adverse outcomes could be the result of mixing the two drugs and so, we will be looking at these in detail later in this article. 

Flucloxacillin, also called Floxacillin in the United States, is an antibiotic that lies within the class of Penicillin. It is a prescription medicine, and hence, cannot be given over the counter. Being a type of Penicillin, those who are allergic to Penicillin should be advised against taking it. Those with liver and kidney problems should also not take the drug.

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Flucloxacillin is available in the form of capsules or a liquid that is drunk. It can also be administered in the form of injections by a physician. It should be taken on an empty stomach – preferably an hour before eating or at least two hours after a meal. This is because the food prevents efficient absorption of the drug, making it much less effective. Its brand name is Floxapen, and it usually treats the infection in a matter of days. Flucloxacillin is primarily used to treat different kinds of bacterial infections. 

Floxacillin or Flucloxacillin is used for the treatment of wounds, skin infections (such as acne, eczema, and scabies), nose and ear infections (for example tonsillitis and otitis externa), and chest infections like pneumonia. It is also used to treat leg ulcer infections, bone infections (such as osteomyelitis), and diabetic foot infections. Blood poisoning, a type of blood infection, is also treated by taking Floxacillin according to the physician’s advice. In children, it is mostly used to treat chest and ear infections. It can be used in conjunction with other medications to treat pneumonia. It kills the bacteria responsible for the infection, by impairing the bonds in the cell wall of the bacteria which make holes into it, eventually curing the infection.

Flucloxacillin is sometimes also given before operations and surgeries, such as heart surgery, to inhibit any infection from developing during the process. Flucloxacillin is resistant to the enzyme called penicillinase produced by the body that breaks down penicillin and causes it to become ineffective. This fact makes Floxacillin a good choice to use for those whose bodies are resistant to other penicillin-type antibiotics. Typically, it is alright to drink alcohol while being on Flucloxacillin medication, however, in moderation only. If the patient notices an upset stomach whilst on the medication, he/she should refrain from alcohol as this will only make it worse. Excessive alcohol may damage the liver faster when on Flucloxacillin.

Flucloxacillin is usually given four times a day, but it can be given thrice as well. No matter the frequency, it is crucial to provide sufficient space between the dosages. Four hours apart is the adequate spacing for the medication. The liquid versions of the drug are to be refrigerated. It is essential to take the complete dose and be careful to not miss any doses. Even if the patient feels better, he/she should not discontinue medication until the prescribed dosage has been completed. An incomplete dosage can result in the infection coming back and causing the relevant bacteria to become resistant to the drug, making it no longer useful in treating the infection. The recommended dose usually ranges from 250 mg to 500 mg four times a day.

As mentioned earlier, Floxacillin takes a few days to work, and the variation depends upon the type of infection. Different antibiotics prescribed for different uses, take different times to treat the respected infection. If it is a skin infection, particularly cellulitis, it can take 5 days to 10 days to improve. Doctors can treat cellulitis by receiving intravenous antibiotics, and after 2 to 3 days they are given Flucloxacillin to take orally. 

Pneumonia can take 8 days (or 3) up to 10 to 15 days to treat – pneumonia acquired from a hospital usually takes longer to treat than that which is not acquired from a hospital. Bone infection may take much longer, for example; if it is a chronic bone infection, this could be 42 to 84 days. That said, Flucloxacillin is typically given for 5 days to 7 days, and taking it for longer than 14 days can cause severe liver damage, among other side effects. Therefore, the physician will prescribe the medication according to the infection and its severity.

Like all drugs, some people consuming Flucloxacillin will experience side effects. Not everyone who has consumed would experience side effects, but some side effects can be common. More than 1 in a hindered people suffer these symptoms. The common side effects of Flucloxacillin include feeling sick or nauseous, vomiting, diarrhoea, bloating, and indigestion. It is advised to see a doctor if these side effects persist. 

More serious side effects of Flucloxacillin are experienced by less than 1 in 1000 people. Although diarrhoea is a common symptom, if you see blood or mucus as well, and you are experiencing muscle cramps, you should see a doctor. Even extreme diarrhoea for 4 days without blood or mucus could be a cause for concern. 

Pale feces and dark urine, pale/ yellow eyes, and skin can indicate liver problems. These problems include jaundice or hepatitis. Bruising or discoloring of skin and joint muscle pain, are also serious symptoms that require a doctor’s assessment. These serious side effects could take up to two months to experience. 

Rarely, people could also experience inflammation of the large intestines which could be the cause of diarrhoea. One may also experience a fluctuation in the number of white blood cells or platelets in the blood. 

In even more rare cases, one may get an allergic reaction. You must seek medical assistance if you experience the following: 

  • A skin rash could include itchy, red swollen blistered, or peeling skin. 
  • Wheezing 
  • Tightness in chest or throat 
  • Trouble breathing or talking
  • Face, mouth, lips, tongue, or throat start swelling 

These signs indicate an allergic reaction and it is important to seek urgent help and treatment. It is important to read and go through the leaflet that comes with the medicine. 

Generally, there is no special warning against consuming alcohol with Flucloxacillin. It does not specifically impact the medicine itself. However, if you’re experiencing any of the symptoms such as a stomach ache or an upset stomach while taking Flucloxacillin, it would be wise to steer clear of alcohol. Alcohol can make the effects worse. Consuming alcohol with Flucloxacillin could also exacerbate liver damage leading to more severe issues. 

Combining alcohol with antibiotics like Flucloxacillin is considered relatively safe, there are no known reactions between the two which could be harmful. It also depends on the type of antibiotics being consumed, as only in rare cases do antibiotics react with alcohol. It seems sensible to try and avoid alcohol when one feels ill or is on medication. As discussed earlier, it is wise to lead the bottle or the medicine pamphlet to ensure that the drugs are not being abused. 

Some believe that taking alcohol while on antibiotics is likely to get you drunker and more spaced out. Therefore it is advised that even when consuming alcohol with flucloxacillin, alcohol should be consumed in moderation. It could however the effectiveness of the drug and even weaken one’s immune system, making it hard for the body to fight against the infection. Therefore, although you may consume alcohol while taking flucloxacillin, it is advised to be careful and try to avoid it. 

Let us now consider the possible dangers of mixing alcohol and flucloxacillin. As mentioned above, mixing both is not potentially harmful per se, but it is best to remain careful. Alcohol in itself can have serious side effects and so can flucloxacillin. A feeling of dizziness could take over if you are experiencing the side effects of flucloxacillin. 

Alcohol on its own can pose a serious threat to the liver and kidneys, and consuming large amounts with an antibiotic which itself can cause liver issues, seems to be a scary scenario. Although the mixture of the two drugs cannot cause liver failure on its own, it surely can increase the risks and chances of damaging one’s liver, lead to issues such as jaundice or hepatitis. If consuming flucloxacillin makes you feel drowsy or dizzy, it is best to avoid alcohol and if you have consumed alcohol and are experiencing such effects, then you must not operate any heavy machinery or drive. 

As discussed earlier, an allergic reaction can be quite dangerous. So, if one combines the two drugs and experiences signs of an allergic reaction, immediate medical help should be sought as the situation can get life-threatening. 

Combining alcohol with flucloxacillin does not necessarily hinder the effectiveness of the antibiotic, but it can slow down the time your body needs to recover from the infection. When one is sick, hydration is important, and consuming alcohol has the opposite effects, so it is better not to consume alcohol. This can slow down your recovery process. 

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Some people might think that skipping a dose of antibiotics and taking alcohol instead could prevent any harmful side effects of mixing the two or consuming the two drugs together, however, this is not how it works. The antibiotic remains in your system for days, and skipping a dose would only mean hindering your set course of antibiotics and slowing down your recovery. If you stop taking antibiotics just to consume alcohol, or if you skip a dose or two, what it essentially does is, that it will increase your chances of developing a bacterial or fungal infection, or the infection you’re trying to fight, could return. 

Yes, it is possible to overdose on Flucloxacillin and can result in some serious consequences. The following guidelines, if not taken into consideration and ultimately overdosed upon, can cause serious side effects; 

Dose for Adults: Every 6 hours, take 250 mg.

Dose for a Child: Half of the adult dosage for children aged 2 to 10 years.

For children under the age of two, a quarter of the adult dose is recommended.

If you forget to take a dose, when your next dosage is approaching, skip the dose you missed and take your next dose when it is due. DO NOT take twice the dose to make up for the missed one. Otherwise, take it as soon as you recall and then resume your regular medication regimen. 

If the guidelines above are now followed, and if, for instance, instead of a 250mg dose, a double dose is consumed (for adults), and this practice is carried out routinely, it can result in an overdose and inevitably, severe side effects and consequences. In any case, it is best advised to consult your doctor or pharmacist if you’re not sure what to do.

Flucloxacillin cures infections in the majority of individuals, however, it can produce adverse effects in some. If you have any side effects while taking Flucloxacillin contact your doctor or pharmacist immediately and promptly. 

Flucloxacillin can cause serious side effects if one overdoses on it; it can damage the liver severely, cause the skin and whites of the eyes to become yellow. This is especially common in elderly individuals and those who have been taking it for longer than 14 days. If you detect any yellowing of your eyes or skin, call your doctor immediately.

Some exceptionally uncommon adverse effects (up to 1 in 10,000 people) are the rare occurrences of blood and fluid abnormalities (high anion gap metabolic acidosis), which happens when plasma acidity rises when flucloxacillin and paracetamol are used together, usually in the presence of risk factors (see Before you take Flucloxacillin). Shortness of breath, wheezing, or troubled breathing; skin rash, itching, or hives; swelling of the face, lips, tongue, or other parts of the body are also rare side effects. You may have had a severe allergic response to Flucloxacillin if you suffer any of these adverse effects.

Symptoms of overdose of Flucloxacillin include oral thrush (white, hairy painful tongue and mouth); feeling ill or vomiting; stomach discomfort, diarrhoea; vaginal thrush is a bacterial infection that affects the female reproductive system (sore and itchy vagina, vaginal discharge). Flucloxacillin can cause the aforementioned adverse effects but it is important to note that these are usually minor and only last a few hours. 

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If you observe any of these following symptoms, call your doctor or go to the local hospital’s Accident and Emergency Department as these are most likely not minor and need immediate attention; 

fatigue, headaches, being short of breath when exercising, dizziness, and appearing pale; bleeding or bruising more readily than usual;  recurrent infections such as fever, chills, sore throat, or mouth ulcers; yellowing of the eyes or skin (jaundice); painful, swollen joints; dark or murky urine, blood in the urine; painful muscles, muscular soreness, or weakness that is not induced by activity, severe stomach pains; watery and violent diarrhoea, which may be bloody.

It is important to note that even if the symptoms appear several weeks after you stopped taking Fluclolaxcillin, call your doctor immediately. Other side effects that aren’t included here may occur in certain patients. If you experience any other side effects, contact your doctor. This list of probable side effects should not concern or stress you. None of these are certain to happen to you. 

The question that then comes to mind is; How to Handle Side Effects?

The answer is; 

If you’re feeling unwell (nausea), eat simple meals and avoid rich or spicy foods.

If you’re ill (vomiting) or diarrhoea, drink plenty of fluids, such as water or squash. If you’re sick, take tiny, regular sips to avoid dehydration. Peeing less frequently than usual or urine with a strong odour are both signs of dehydration. Do not take any additional medications without first consulting a pharmacist or doctor.

Avoid meals that generate a wind to avoid bloating and indigestion (like lentils, peas, beans, and onions). Smaller meals, slow eating and drinking, and frequent exercise are all good ideas. Simethicone, a pharmacy medication, can also assist.



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