Levofloxacin - Uses, Dosage, Side Effects, Drug Warnings, and Precautions

Overview

Levofloxacin is a fluoroquinolone antibiotic medicine that is used to treat bacterial infections. This drug is used in the treatment of various bacterial infections. Levofloxacin was carefully prescribed to determine the actual causative organ to decrease the development of drug-resistant bacteria and maintain the efficacy of the drug. It is available in tablets, injections, or oral solution forms. The drug is stored at nearly fifteen degrees Celsius in a bottle. Patients are advised to follow proper precautions and inform the physician about their medical history to the physician to avoid any complications of administering the drug.

How Does Levofloxacin Work?

Levofloxacin works by inhibiting bacterial enzymes. Two bacterial enzymes, Topoisomerase and DNA gyrase. These enzymes promote the supercoiling of the DNA and initiation of transcription. All these processes help in cell division and further replication. And hence, the drug acts on these enzymes and blocks the replication of DNA (deoxyribonucleic acid) and inhibits cell division, and leads to cell death. Levofloxacin works on bacteria-causing diseases, such as the following:

• Nosocomial pneumonia.

• Acute sinus infection.

• Community-acquired pneumonia.

• Chronic bronchitis.

• Complicated and uncomplicated skin infections.

• Prostate infection.

• Inhalational anthrax.

Available Doses and Dosage Forms:

• Levofloxacin is available in the form of tablets, oral solutions, and injections.

• Levofloxacin tablets are available in doses of 250 milligrams, 500 milligrams, and 750 milligrams.

• Levofloxacin in oral solution is available at 25 milligrams per milliliter. The solution is available in clear yellow to greenish yellow solution.

• Levofloxacin Injection is available in single-use vials ranging from a color of clear yellow to clear greenish yellow.

Warnings:

• Increased risk of tendonitis and rupture of the tendon is seen and is higher in older individuals and individuals with kidney, lung, and heart problems. The drug is to be discontinued if any changes in the tendon occur.

• Muscle weakness can increase in patients suffering from myasthenia gravis.

• Allergic skin reactions, hypersensitive reactions, and other anaphylactic reactions can occasionally turn fatal, also even after the first dose.

• Renal and hematologic toxicities can occur after multiple doses.

• Effects on the central nervous system include anxiety, convulsions, depression, confusion, and insomnia can also occur.

• The drug is to be discontinued immediately when symptoms of peripheral neuropathy occur.

For Patients:

What Are Bacterial Infections?

Bacterial infections commonly occur in public health. They can show their effect at any site on the body. The bacteria can be transmitted through air, food, water, and other living vectors. Bacterial infections can spread from one person to another by contact, droplet transmission, vectors, or by contaminated food and water. Bacteria can be classified into gram-positive or gram-negative based on their characteristics. Depending on the growth in the presence and absence of bacteria, they are divided into aerobic and anaerobic organisms.

Clinical Symptoms of Bacterial Infections:

• Usually, bacterial infections present with fever, chills, tiredness, nausea and vomiting, abdominal pain, or headaches.

• Based on the site of infection, the symptoms can vary.

• Heart - Chest pain, shortness of breath, high fever, joint pain

• Urinary tract - Burning sensation during urination, lower abdomen pain.

• Lungs - Chest pain, cough, sputum.

• Gastrointestinal tract - Diarrhea, nausea, and vomiting, including stomach pain.

Diagnosis of Bacterial Infections:

Laboratory examination of the sputum, blood, stool, urine, and any secretions.

Treatment of Bacterial Infections:

Treatment usually depends on proper diagnosis. A wide range of antibiotics is available. Choosing the right antibiotic that can act on the bacteria and destroy it forms an important part of the treatment. Bacterial infections have now become resistant to major antibiotics, and hence the physician prescribes the right antibiotic. One such category of drugs is fluoroquinolones which include Levofloxacin. Levofloxacin works on bacteria causing the following diseases such as nosocomial pneumonia, chronic bronchitis, prostate infection, and complicated and uncomplicated skin infections.

Learn More About Levofloxacin-

When and Why to Take Levofloxacin?

Levofloxacin is an antibacterial medication that is advised in adults suffering from infections caused by susceptible and designated bacteria. It is usually prescribed for a week or two, depending on the type of bacteria causing the infection and the severity of the infection.

Following are the respective dosages for each condition:

• Nosocomial pneumonia, acute bacterial sinusitis, complicated skin infections, acute pyelonephritis -750 milligrams.

• Community-acquired pneumonia, chronic bacterial prostatitis - 500 milligrams.

• Uncomplicated urinary tract infection - 250 milligrams.

Things to Inform the Doctor Before Taking Levofloxacin

• Inform the physician about the following issues before taking the medication.

• History of tendon problems.

• Suffering from myasthenia gravis (muscle weakness).

• Episodes of seizures.

• Nerve problems.

• Lack or low potassium in the blood.

• Suffering from rheumatoid arthritis-like joint problems.

• Liver abnormalities.

• Decreased blood sugar or suffering from diabetes.

• All the medication that is being taken, including multivitamin tablets or herbal supplements, is to be informed. Medications such as steroids, antipsychotic medicines, diuretics, Warfarin, etc., are to be informed prior.

What Are the Side Effects of Levofloxacin?

The following are certain serious side effects:

• Serious Allergic Reactions: These include breathing issues, throat tightness, hoarseness, an increase in the rate of heartbeat, and skin rashes. Skin rashes can occur even after a single dose of the drug and is a sign of a serious, complicated reaction to the drug.

• Hepatotoxicity (Liver Damage): Liver damage can present as nausea or vomiting, fever, abdominal pain, loss of appetite, and unusual tiredness can also occur.

• Central Nervous System Effects: Seizures, restless feelings, depression, confusion, anxiousness, nervousness, and continuous headache are a few symptoms that can occur as a result of CNS being affected.

• Infection of the Intestine: Pain, burning, tingling, numbness, and weakness, along with a few symptoms of peripheral neuropathy, can occur.

• Problems in the Joints: Issues with the bones and joints in children can occur. The physician should be informed about any changes.

• Blood Sugar Changes: Levels of blood sugar can decrease when treated with Levofloxacin.

• Nausea, diarrhea, headache, constipation, and insomnia are other common side effects.

How to Use Levofloxacin?

• Levofloxacin is taken at almost the same time every day.

• Plenty of fluids should be taken upon administration of Levofloxacin.

• Tablets of Levofloxacin can be taken with or without food.

• The oral solution of the drug should be taken one hour prior and two hours after eating the food.

• Injection of Levofloxacin is given intravenously (IV) by the doctor.

What Should Be Done if a Dose Is Missed?

Upon missing a dose of Levofloxacin, the drug should be taken as soon as one remembers keeping in mind not to take more than one dose any day. Levofloxacin should not be skipped any day, even if the clinical conditions improve. The prescribed dose should be completed and stopped only when advised by the physician.

What Should Be Done to Treat Levofloxacin Overdose?

In the incidents where Levofloxacin is purposely or accidentally administered in high doses, the stomach should be emptied at first. The patient is kept under observation, and proper hydration is maintained. The drug cannot be removed by dialysis.

Storage:

• Levofloxacin tablets are stored at 15 degree Celsius to 30 degree Celsius in a tightly closed container.

• Oral solution of Levofloxacin should also be stored at the same temperature away from the reach of children.

Avoid Self-Medication:

It is advised not to take the drug Levofloxacin without a proper prescription from a healthcare physician. Patients already using the drug should not be allowed to suggest the same medication to other individuals suffering from certain conditions as there are high chances of drug interactions and complications that cannot be assessed by a common man.

For Doctors:

Indications:

The drug Levofloxacin in oral and intravenous formulations is indicated in adults for treating susceptible bacterial infections, which include upper and lower respiratory tract infections, skin infections, infections of the urinary tract, and prostate and infections affecting other organisms. Oral formulation can also be indicated in children suffering from inhalational anthrax older than six months of age. The ophthalmic formulation is used in the treatment of bacterial conjunctivitis affecting the eye. An inhalational solution is also available, which is used in the management of cystic fibrosis.

Dosing:

The drug Levofloxacin is available in the form of injection solutions that are administered intravenously. Tablets of 750 milligrams, 500 milligrams, and 250 milligrams are available and prescribed based on the type of bacteria causing the infection and the type of the infection, along with the clinical condition of the patient. An ophthalmic solution of dosage 15 milligrams per 1 milliliter is also available and prescribed for bacterial infections of the eye.

Pharmacology:

Mechanism of Action:

The drug Levofloxacin works by inhibiting bacterial DNA synthesis. DNA strands are broken down by inhibiting DNA gyrase which prevents the relaxation of the supercoiled DNA. Levofloxacin acts mainly on gram-positive Penicillin-resistant bacteria compared to gram-negative bacteria. It also acts majorly over the fluoroquinolones in antitubercular therapy. The main concern is drug resistance to Levofloxacin.

Pharmacodynamics:

It has a prolonged duration of action as compared to other antibiotics and hence allows for daily dosing at once or two times a day. It should be, however, used with caution in certain patients with hypokalemia. Few cases of cross-resistance were reported with other fluoroquinolones. Antimicrobial susceptibility patterns are to be considered to ensure proper coverage of the bacteria.

Pharmacokinetics:

• Absorption: The drug Levofloxacin is readily absorbed and distributed in the body. As for bioavailability, if the drug is 99 percent, the intravenous form and oral form of the drug can be used interchangeably.

• Distribution: The distribution volume varies from 74 liters to 112 liters which can denote huge distribution in the body. The drug is mostly distributed in the muscles, liver, kidney, skin, and spleen.

• Metabolism: Hepatic metabolism is done with the drug Levofloxacin and is excreted as such in the urine.

• Excretion: The drug Levofloxacin is eliminated mostly through the renal route. Plasma half-life elimination is nearly six to eight hours following one or multiple doses of the drug.

Toxicity:

There is a low potential for toxicity, and symptoms such as ataxia, dyspnea, ptosis, tremors, and convulsions are also observed. Overdosage of the drug should be done by emptying the stomach and other supportive measures.

Non-Clinical Toxicity:

• Carcinogenicity: Levofloxacin did not show any symptoms of photo carcinogenicity as it did not decrease the time of tumor development of skin tumors. Many assays like Ames bacterial mutation assay and chromatid exchange assay were performed in which the drug was determined to be non-mutagenic in nature.

• Impairment in Fertility: No fertility impairment or alteration in the reproductive potential has been seen.

Warnings and Precautions:

• Tendinopathy and Tendon Rupture: There is a high risk of tendon rupture and inflammation of the tendon in almost all ages. Rupture of the certain tendon will require surgical repair. In older patients over the age of 60 years, the risk of tendonitis is severe. In certain patients with kidney, lung, and heart transplants, those using corticosteroid drugs are also at higher risk. Effect on the tendon can occur during and after the completion of treatment with Levofloxacin. Drugs and drug dosages are changed when the patient informs about the first symptom that occurs.

• Exacerbation of Myasthenia Gravis: Drugs having neuromuscular blocking activity can increase muscle weakness in patients suffering from myasthenia gravis. The drug Levofloxacin is one such drug that should be avoided in patients suffering from myasthenia gravis.

• Hypersensitivity Reactions: Anaphylactic and hypersensitivity reactions are seen in patients taking Levofloxacin. Such reactions can occur soon after the first dose. The symptoms can also include cardiovascular collapse, seizures, shock, loss of consciousness, angioedema, dyspnea, and various other skin reactions.

• Other Reactions: Rashes, high fever, severe dermatologic reactions, arthralgia, myalgia, pneumonitis, hepatitis, jaundice, and renal failure are certain other reactions that are serious and sometimes turn into fatal reactions.

Contraindications: Patients with known hypersensitivity to quinolone antibacterials or the drug Levofloxacin are contraindicated from the administration of the drug.

Drug Interactions:

• Chelation Agents: Antacids, Multivitamins, Metal cations, and Sucralfate: Multivitamins and sucralfate interfere with the absorption of Levofloxacin in the gastrointestinal tract, which results in lowering systemic levels. In order to avoid this, all the agents like antacids, multivitamins, sucralfate, and metal cations should be administered at least two hours prior and two hours after taking the drug, Levofloxacin orally. Levofloxacin in injection form should not be co-administered along with solutions containing chelating agents.

• Warfarin: Certain cases were reported that showed the effect on the bleeding time and prothrombin time. Anticoagulation tests should be monitored closely when Levofloxacin is administered along with warfarin. Any bleeding symptoms or adverse reactions should also be noticed during this period.

• Antidiabetic Agents: Blood glucose disturbances like hyperglycemia and hypoglycemia can be seen in patients taking treatment for diabetes. Co-administration of the drug Levofloxacin should be carefully done with antidiabetic agents.

• Non-Steroidal Anti-Inflammatory Drugs: CNS stimulation and seizures can occur when non-steroidal anti-inflammatory drugs are administered along with Levofloxacin.

• Theophylline: No major effect on theophylline was observed on administering along with the drug Levofloxacin. With the prolonged elimination half-life, increased levels of serum theophylline can occur. And hence appropriate dosage adjustments of Levofloxacin are made. Other adverse reactions can also occur without any change in serum theophylline levels.

• Cyclosporine: Elevated serum levels of Cyclosporine are reported when administered along with Levofloxacin. Minute changes can occur in which the differences are of no major importance, and no adjustment of the dose is required when Levofloxacin and Cyclosporin are co-administered.

• Digoxin: No significant changes occurred due to the administration of Digoxin and Levofloxacin concomitantly. Hence no dose adjustment is required.

• Probenecid and Cimetidine: Similar to the effects of Cyclosporine and Digoxin, no major effects are observed with Probenecid and Cimetidine.

Other Specifications:

• In Pregnant Women: When administered in trials on animals, no teratogenic effect was observed. The highest recommended dose, as high as 25 milligrams per kilogram of body weight, can be administered when the benefit of the drug can be considered on par with the risk to the fetus.

• In Lactating Women: Levofloxacin is assumed to be excreted in human milk, and hence care should be taken whether to stop nursing the infant or to stop administering the drug. The choice should be made based on the necessity of the drug to the mother.

• In Pediatrics: Arthralgia and myalgia frequently occur in pediatric patients on treatment with the drug Levofloxacin. Vomiting and diarrhea are reported in pediatric patients in whom the drug Levofloxacin is administered.

• In Geriatrics: Severe tendon disorders like rupture of the tendon can occur as a risk in older patients as well as those receiving corticosteroid therapy. Fatal hepatotoxicity reactions occurred majorly in older patients.

• Renal Impairment: Levofloxacin clearance is reduced, and the half-life of the drug is prolonged in patients with renal impairment. Dose adjustments are required to avoid accumulation in such patients. As the drug cannot be eliminated from the body either through dialysis, additional administration of supplemental doses of Levofloxacin is not required.

• Hepatic Impairment: Studies show that Levofloxacin is not affected by an impairment of the liver. As there is limited metabolism of the drug, the pharmacokinetics of the drug are not affected by hepatic impairment.