Are you taking antibiotics to cure your urinary tract infection? And are you worried about the side effects of these antibiotics? Then this article is for you. Antibiotics are the mainstay of UTI management.
Like most drugs, no antibiotics are free from the risk of developing side effects. In this article, we will discuss the common side effects of the most common antibiotics used in UTI. The management of such side effects will be discussed too.
What are the most common antibiotics used in UTI?
The choice of antibiotics depends on the age, physical condition, disease severity, suspected organisms, and the drug-resistant pattern of that region. So, a wide range of antibiotics is used in urinary tract infections. Here is a list of the most common antibiotics used in UTI.
- Oral antibiotics
Ciprofloxacin
Levofloxacin
Nitrofurantoin
Cefixime
Cefuroxime
Cotrimoxazole
Azithromycin
- Injectable antibiotics
Ceftriaxone
Meropenem
Gentamicin
The injectable form of ciprofloxacin is also used.
In mild to moderate infection, your doctor will usually prescribe oral drugs. But in severe infection and debilitated patients, injectable drugs are often required.
What are the common side effects of UTI antibiotics?
First of all, you have to remind that, not all patients suffer from every side effect of a drug. You may even develop no side effects at all. If you check the prescribing information of any medicine, you will find a long list of unwanted effects.
But, the list encompasses all effects which are found even in <1% of the consumers. Even the most common side effects are found among 10-20% of the users. So, don’t worry about long the list of side effects. Here we are going to discuss some important side effects.
- Nausea and vomiting
These are the most common side effects of all antibiotics. You may suffer from nausea and vomiting after taking any antibiotic. However, these are usually mild and subside soon after completion of the regimen.
- Diarrhea
Loose motion or diarrhea is a common side effect of broad-spectrum antibiotics. Do you know what is meant by the term ‘broad spectrum?
The antibiotics which are effective against a wide range of microorganisms from different groups are called broad-spectrum ( e.g. cefuroxime, ceftriaxone, ciprofloxacin, etc). This is a good property. But can you realize the negative side?
If you take a broad-spectrum antibiotic, it will not only kill the UTI pathogen but also other bacteria in the body. Especially the good bacteria, which are normal inhabitants of your intestine, are killed.
There are some opportunistic pathogens ( Clostridium difficille) in the gut that can’t grow due to the presence of normal bacterial flora. But they are often resistant to conventional antibiotics.
When the normal colony is destroyed, they grow up and lead to diarrhea. It is found in 16%patients taking cefixime, up to 11% with cefuroxime, 5% with levofloxacin, and 3% with ceftriaxone.
- Allergic reaction
Not only antibiotics, but any drug may also lead to allergy. Cotrimoxazole is well known for its allergic property. The most common symptoms are skin rash, itching, runny nose, etc.
In most cases, these are mild. But life-threatening anaphylaxis may happen if you are unlucky (e.g. penicillin reaction). If you have known allergies, talk to your doctor beforehand to avoid complications.
- Abdominal pain
Alteration of normal bacterial flora as described above may lead to abdominal pain and discomfort. In addition, some antibiotics irritate the gastric wall leading to upper abdominal pain, and almost all of the UTI antibiotics have that characteristic.
- Headache
Headache is a very common side effect of most antibiotics. About 6% of patients taking levofloxacin suffer from headaches. It is also found in <1% cases with nitrofurantoin, ciprofloxacin, and ceftriaxone, But it is usually mild and not reported.
Patients with prior central nervous system (CNS) disease, renal insufficiency, and advanced age may develop a severe headache.
If the headache is intractable or associated with convulsion, it may be a sign of antibiotic-associated neurotoxicity. Such cases are reported with a wide range of antibiotics including, gentamicin, cefuroxime, ceftazidime, penicillin, carbapenem, ampicillin, etc.
But, those are extremely rare and you don’t need to worry much. If you suspect any problems, talk to your doctor immediately.
- Dizziness
Ciprofloxacin, azithromycin, and gentamicin may cause dizziness. Levofloxacin and nitrofurantoin are also reported to cause dizziness.
- Sleep disturbance
Insomnia and restlessness are found with many antibiotics. The quinolone group is notorious for affecting human sleep. About 4% of patients taking levofloxacin complain of insomnia. Ciprofloxacin was even reported for causing nightmares. However, this is very rare.
- Fatigue and drowsiness
You may feel tired or drowsy after taking antibiotics. This is called antibiotic-associated fatigue. Antibiotics like ciprofloxacin, azithromycin, amoxicillin, nitrofurantoin, etc may cause fatigue and drowsiness.
These effects may be potentiated if other drugs with similar side effects like antihistamines, anti-depressants, anxiolytics, etc. are taken simultaneously. But it is not usually severe and often associated with disease severity.
- Fungal infection
This is also related to the use of broad-spectrum antibiotics like ceftriaxone, meropenem, levofloxacin, etc. As we have already discussed, normal bacterial flora is also killed by antibiotics.
The normal flora inhibits the growth of fungus over skin and mucosa (e.g. oral cavity, vagina). When they are destroyed, the fungus gets a chance to grow and cause infection.
- Immunosuppression
This is rare but experienced by some patients. It is manifested by reduced white blood cell count. In most cases, patients face no problems at all other than an abnormal blood test.
- Reaction at the injection site
Some antibiotics are administered parenterally as an intravenous or intramuscular injection. You may suffer from local reactions like swelling, redness, tenderness, etc at the site of injection.
This is very common with ceftriaxone. More than 10% of patients suffer from the local reaction after intramuscular injection of ceftriaxone.
How to deal with the side effects of antibiotics?
Are you getting afraid of antibiotics after reading the side effects? Don’t worry. As we have described, only a few patients will experience those. Now we are going to discuss how can we avoid and reduce the side effects.
First of all, follow the prescription of your doctor properly. Be careful about the dosage schedule and formulation. Take the right drug and at the right time.
When buying the medicine, check if your pharmacist has given the right medicine for you. Talk to your doctor and pharmacist, if they have any special advice for the prescribed antibiotic.
Secondly, to reduce abdominal pain and discomfort, take the antibiotic with or after a meal. Most antibiotics used in UTI are better tolerable after a meal except for Azithromycin which should only be taken one hour before meals or two hours after them.
Gastric irritation will be less if taken in such a way. Take plenty of water and high fiber diet. This will help to reduce nausea and vomiting too.
Thirdly, if you have a known drug allergy, talk to your doctor. Some antibiotics share common allergic properties. For example, if you have an allergy to any sulfur compound or drug, you may develop an allergy to cotrimoxazole (which contains sulfur compounds too).
It is seen that 10% of the penicillin-sensitive patients are allergic to the cephalosporin group of antibiotics (e.g. ceftriaxone, cefixime, etc). If you already have developed an allergic reaction, contact your doctor.
If you have only mild symptoms like itching, an antihistamine (e.g. fexofenadine, cetirizine, loratadine, etc) will be enough. However, if you suffer from widespread skin rash or desquamation, low blood pressure, reduced micturition, etc. visit your doctor immediately. These may be signs of severe anaphylactic reaction and hospital admission will be required.
Fourthly, mild antibiotic-associated diarrhea can be managed with oral rehydration saline only. But if you develop severe diarrhea, the antibiotic may need to be changed. If required, your doctor may add another antibiotic like Vancomycin to kill the Clostridium difficile.
The fifth, always receive healthcare services from a qualified person. If your doctor prescribes intramuscular/intravenous antibiotics, but you don’t want to stay in the hospital, contact a qualified medical assistant or nurse for home service.
Don’t get your drug administered by a quack. Though it is not always preventable, adopting the right technique will reduce the risk of local reaction.
Sixthly, take adequate rest to avoid problems related to dizziness, fatigue, or sleep disturbance. Avoid alcohol intake as it may worsen fatigue and drowsiness.
If you are taking any other drugs that may potentiate the problem, talk to your doctor. He may choose an alternative or change the dosage schedule to minimize the problems. For example, taking levofloxacin in the morning or noon will reduce the risk of insomnia.
And at last, maintain good personal hygiene to avoid fungal infection. If you have already developed fungal infections, topical antifungal agents like fluconazole will help to treat.
For more information about UTI antibiotics please visit this article.
How do these antibiotics interact with other drugs?
Drug interaction is a very common but overlooked fact. Nowadays, patients often take multiple drugs for different illnesses. Interactions among these drugs may enhance or reduce the action of others.
This is a complex subject and a bit difficult to understand for a non-medical person. We will discuss in brief some common interactions of the antibiotics used in UTI. It will help you avoid unnecessary events.
Ciprofloxacin and levofloxacin are members of the fluoroquinolone group that are commonly used antibacterial agents in UTI management. But the absorption of fluoroquinolones may be impaired by some mineral supplements.
Multivitamin and multimineral supplements are available without prescription and are widely used. You may think that this is a very simple drug and forget to mention it when talking to the doctor. But, if your doctor advises ciprofloxacin, it may not be absorbed adequately leading to low blood concentration. Ultimately, it may result in treatment failure.
The antibiotics of the cephalosporin group (cefixime, ceftriaxone, cefuroxime, etc) are usually well tolerated. But if you are taking anticoagulant drugs like warfarin for any cardiovascular illness, you need to be careful.
Warfarin reduces blood clotting factors by inhibiting some anticoagulant factors. These antibiotics potentiate the action of warfarin and increase the risk of spontaneous bleeding. To avoid this complication, your doctor may reduce the dose of warfarin.
The interaction of antibiotics with oral contraceptive pills is well known. The contraceptive effect of oral pills is reduced when taken with many common antibiotics. Rifampin is the most notorious antibiotic that leads to contraceptive failure. But it is not used in treating UTI.
Luckily, the risk is lower with other antibiotics, but not zero. So, it is better to use an alternative method of contraception when taking antibiotics.
Do you take antacids frequently to reduce gastric acidity?
Be careful if you need to take antibiotics like ciprofloxacin due to UTI. Some antacids contain aluminum, calcium, sucralfate, etc. which reduce the absorption of ciprofloxacin leading to treatment failure. The same occurs with levofloxacin too.
The concentrations and actions of some anti-epileptic and anti-arrhythmic drugs may be increased by most of the antibiotics especially levofloxacin. It may increase the side effects of such drugs.
Antibiotics like cefuroxime may increase the nephrotoxic effects of painkillers, furosemide, and gentamicin. Especially if you have known kidney disease, any antibiotics must be used cautiously.
Do you have diabetes? If you are taking oral antidiabetic drugs like Glibenclamide, it may interact with levofloxacin resulting in altered blood glucose levels. Inform your doctor beforehand.
If you are suffering from chronic inflammatory disease like rheumatoid arthritis, you may need to take immunosuppressive drugs like methotrexate. And it may increase the risk of urinary tract infection too. But, the problem is methotrexate may interact with some antibiotics like cotrimoxazole, penicillin, etc. It increases the toxicity of methotrexate. So, inform your doctor in advance.
The list can be further extended, but it will be more complex. You don’t need to boil your brain with such complex discussions. Just mention every drug you take, when talking to your doctor. He will sort out the interactions and choose the best possible antibiotic for your UTI.
How do UTI antibiotics affect your pregnancy?
Urinary tract infection is a common pathological event during pregnancy. To treat UTI, you need to take anti-bacterial agents. But, all antibiotics are not safe in pregnancy.
Safer antibiotics for UTI during pregnancy
- Cephalosporins are considered the best choice during pregnancy. It includes cefixime, cefuroxime, ceftriaxone, etc.
- Azithromycin
- Penicillin analogs like amoxicillin
- Nitrofurantoin
Unsafe antibiotics for UTI during pregnancy
- Cotrimoxazole
- Ciprofloxacin
- Gentamicin
- Levofloxacin
The latter group of drugs may adversely affect your pregnancy outcome. They may cause birth defects or even abortion. Especially the first trimester of pregnancy is the riskiest period. Don’t forget to tell your doctor that you are going to be a mother.
Even when you have just missed a period, and are not sure about the conception yet, inform your doctor. Do a urine pregnancy test if required. It takes just a few minutes but can save your upcoming baby.
Do antibiotics irritate the bladder?
It is very unlikely that antibiotics will cause bladder irritation leading to frequent urge to urinate. A lot of drugs act on the bladder and cause urinary disturbances. And many drugs act on the kidney leading to excessive urination(i.e. anti-hypertensives and anti-psychotics).
These drugs are enlisted by different authors in different journals. But antibiotics are not found in those lists. The side effects of different antibiotics including macrolides and nitrofurantoin were evaluated. But no reliable data were found regarding the occurrence of frequent urination after taking nitrofurantoin or other antibiotics.
However, few patients complain of frequency, urgency, etc after using nitrofurantoin. But such reporting is rare and the relationship is still not established. It is unclear that whether these unusual symptoms are due to antibiotics or a result of the disease process of UTI or other comorbidities.
The fact is urinary frequency may persist even after taking antibiotics. Sometimes, it happens that the patient starts antibiotics at the earlier stage of UTI when bladder irritation was less. But it increased later and persisted unusually bit longer. It was actually a normal disease course, but patients accused nitrofurantoin to cause it.
Another important event is drug-induced nephropathy (kidney injury). Some antibiotics like macrolides, penicillin, methicillin, carbenicillin, etc may cause kidney injury. And the kidney disease may initially present with excessive urination.
Do antibiotics cause urinary tract infections?
What do you think? Is it possible? The effect of an antibiotic is to kill bacteria. It may fail to do the job, the infection may persist even after taking the antibiotic. But the antibiotic will not promote the occurrence of UTI.
However, hemorrhagic cystitis is reported very rarely after taking penicillin. But this is not an infective disease meaning that it’s not a urinary tract infection.
That’s all about the antibiotics used in UTI for now. Hope you got some idea about these topics. To know more, talk to your doctor. You can reach us to clarify any confusion. Thanks for reading with patience.