Overview
Cefadroxil belongs to a class of medications called cephalosporins and is used in treating bacterial infections of the throat, tonsils, skin, and urinary tract. Cefadroxil must be used only when the infections are proven or otherwise strongly suspected to be caused by bacteria to maintain the drug's effectiveness and decrease the development of drug-resistant bacteria. The drug was patented in 1967 and was approved for medical use in 1978. It is intended for oral administration and was approved by the United States Food and Drug Administration (USFDA) on 26 March 2003.
Indications of Cefadroxil
Culture and susceptibility tests must be done before and during the treatment with Cefadroxil. Renal function studies may also be performed if required. Cefadroxil is indicated in the following conditions:
-
Tonsillitis and pharyngitis, caused by Streptococcus pyogenes.
-
Skin infections caused by Streptococci and Staphylococci species.
-
Urinary tract infections (UTIs) are caused by microorganisms such as E. coli, Klebsiella, and P. mirabilis.
Contraindications of Cefadroxil
Cefadroxil is not recommended in patients with known allergy to Cephalosporin antibiotics.
Available Doses and Dosage Forms
Cefadroxil is a powder for oral suspension, 500 mg (milligram) capsules, and one-gram tablets. It is acid-stable and can be orally administered without regard to meals. However, when taken along with food, it may help overcome gastrointestinal issues. The dosage of Cefadroxil is as follows;
-
For pharyngitis and tonsillitis in adults, one gram per day as a single dose or as divided doses (twice daily) for ten days. 30 mg/kg/day is a single or equally divided dose (every 12th hour) for children.
-
For skin infections in adults, one gram per day as a single dose or as divided doses (twice daily). For children, 30 mg/kg/day in equally divided doses (every 12th hour).
-
For urinary tract infections such as cystitis, in divided doses, one or two g (grams) per day as a single or twice daily. Two g per day in divided doses, twice daily for all other urinary tract infections. The recommended daily dose in children is 30 mg/kg/day as divided doses every 12 hours.
-
Cefadroxil must be administered for at least ten days in case of beta-hemolytic streptococcal infections.
-
The dosage must be adjusted based on the creatinine clearance rate for patients with renal disorders to avoid drug accumulation.
Warning and Precautions
-
Before initiating the treatment, a careful inquiry must be made to determine if the patient has previously experienced any hypersensitivity reactions to Cefadroxil, other cephalosporins, penicillins, or any other drugs. The drug must be discontinued immediately in case of allergic reactions, and serious hypersensitivity reactions must be treated with Epinephrine and other emergency measures.
-
Most antibacterial drugs, including Cefadroxil, can cause pseudomembranous colitis, which may be mild or severe. It is mainly due to the alteration of the normal flora, which leads to the production of toxins by the overgrowth of Clostridia species. Therefore, this diagnosis must be considered in patients reporting diarrhea after administering these medications. Mild cases can be managed by discontinuing the drug, but moderate to severe cases are treated by other antibacterial drugs, fluid and electrolyte support, and protein supplementation.
-
Long-term use of Cefadroxil can lead to the overgrowth of nonsusceptible microorganisms. Therefore, patients must be carefully monitored, and appropriate measures must be recommended in case of superinfection.
Adverse Effects of Cefadroxil
-
Pseudomembranous colitis can be seen during or after the treatment. Some of the rare adverse effects include nausea, vomiting, dyspepsia, and diarrhea.
-
Hypersensitivity reactions such as urticaria, rash, angioedema, and pruritus can occur in patients during the treatment with Cefadroxil.
-
Many cephalosporins can trigger seizures in patients with renal impairment if the dose of Cefadroxil is not reduced. The drug must be discontinued immediately, and anticonvulsant medications may be given if required.
For Patients
What Are Bacterial Infections?
Infections or diseases caused by single-celled organisms that multiply or release toxins in the body are called bacterial infections. They can affect any body part, such as skin, brain, blood, respiratory tract, and urinary tract. They greatly impact public health as they are transmitted through water, air, food, or bodily fluids. Some examples of bacteria include Staphylococcus, Streptococcus, Escherichia coli, Salmonella, and Klebsiella. Bacterial infections usually resolve with appropriate treatment. However, when left untreated, it can become severe and cause further complications.
What Is Cefadroxil?
Cefadroxil is a long-acting, broad-spectrum antibiotic, which belongs to the class of medicines called Cephalosporin antibiotics. It is a prescription medicine and hence must be taken exactly as directed by the doctor. Using this medicine when not required can increase the risk of resistance to the drug when infected later. This medicine is not useful for colds (common cold), flu, and other viral infections.
What Are the Uses of Cefadroxil?
Cefadroxil is used for the following indications;
-
Skin infections.
-
Throat or tonsil infections.
-
Urinary tract infections.
-
It can also prevent heart valve infection in certain patients allergic to the penicillin group of drugs, have a heart condition, and are undergoing dental or upper respiratory tract treatment.
How Does Cefadroxil Work?
Cefadroxil is water-soluble; it binds to specific proteins and destroys and prevents bacteria growth by inhibiting cell wall synthesis. It is effective against different types of gram-positive and gram-negative bacteria. The patient may feel better after the first few days of treatment. However, the medication must be taken as prescribed to be completely treated, as the bacteria can become resistant to antibiotics.
What Is the Dosage of Cefadroxil?
Cefadroxil must be taken exactly as instructed by the doctor. The dose of Cefadroxil and the type of infection differs among patients. It can be taken with or without food.
-
The recommended dose for urinary tract infections in adults is one or two g/day as a single or divided dose (twice daily). For skin infections, the dose is one gram per day as a single or divided dose (twice daily). In cases of tonsillitis or pharyngitis, the recommended dose is one gram per day as a single or divided dose (twice daily) for ten days.
-
In children, the treatment duration for streptococcal infections is around ten days. The recommended dose for urinary tract infections and skin infections is 30 mg/kg/day as divided doses every 12 hours. In cases of impetigo, tonsillitis, or pharyngitis, the recommended dose is 30 mg/kg/day as a single dose or as divided doses every 12 hours.
What Are the Side Effects of Cefadroxil?
Some of the side effects of Cefadroxil include;
-
Vomiting.
-
Diarrhea.
-
Genital itching.
-
Swelling of face, eyes, lips, tongue, and throat.
-
Rash.
-
Difficulty breathing or swallowing.
-
Sore throat.
-
Chills.
-
Yellowish discoloration of eyes and skin.
-
Pain in the upper part of the abdomen.
-
White or clay-colored stools.
-
Dark urine.
What Are Some of the Important Instructions About Cefadroxil?
-
Cefadroxil can reduce the effectiveness of live bacterial vaccines such as typhoid vaccine. Hence, the healthcare provider must be informed before vaccinations or immunizations.
-
Cefadroxil may cause false positive readings with certain diabetic urine testing products, such as cupric sulfate, which can affect the results of some lab tests. Therefore, the healthcare provider must know that the patient is using this medication.
What Must the Patient Inform the Doctor Before Taking Cefadroxil?
-
Patients must inform the doctor if they suffer from or have ever had colitis (swelling in the lining of the large intestine), diarrhea, other gastrointestinal disorders, kidney diseases, or any other medical conditions before taking Cefadroxil.
-
Patients must tell the doctor if they are allergic to Cefadroxil, other antibiotics, or any other medications before starting the treatment.
-
Female patients must inform the doctor if they are pregnant or planning to become pregnant or lactating before taking Cefadroxil.
-
Patients must inform the healthcare provider if they take any other medications, herbal medicines, vitamins, nutritional supplements, or over-the-counter medicines before taking Cefadroxil.
-
Dietary Considerations: A normal diet can be followed during the treatment unless specified by the doctor.
-
Missed Dose: The missed dose must be taken as soon as remembered. However, if it is almost time for the next dose, the missed dose can be skipped, and the regular dosing schedule must be followed. A double dose must not be taken to compensate for the missed one.
-
Overdose: In case of an overdose of the drug, or the patient is experiencing difficulty in breathing or seizures, the healthcare provider or a hospital must be contacted immediately.
-
Storage and Handling: The medication must be stored at room temperature in its original container, tightly closed and away from children. The suspension must be tightly closed and refrigerated. Unused and unneeded medications must be carefully disposed of in special ways to ensure that children or pets do not consume them.
For Doctors
What Are the Pharmacological Aspects of Cefadroxil?
Mechanism of Action
Cefadroxil, a semisynthetic cephalosporin, similar to all other beta-lactam antibiotics, binds to certain penicillin-binding proteins (PBPs) which are situated inside the bacterial cell wall and inhibit the third and the last phase of bacterial cell wall synthesis. Bacterial cell wall enzymes such as autolysins medicate the cell lysis, and Cefadroxil is known to interfere with an autolysin inhibitor.
Pharmacodynamics:
Cefadroxil is an oral first-generation cephalosporin used to treat bacterial infections and whose action mainly depends on the concentration achieved in the blood. Like all cephalosporins, it acts through time-dependent killing. Hence, it is vital to maintain a sufficient concentration of antibiotics above minimum inhibitory concentration (MIC) in blood over prolonged periods to achieve significant destruction of the microbes. Cefadroxil has a relatively longer half-life and slower renal elimination in comparison to other first-generation agents needing less frequent dosing.
Pharmacokinetics
-
Absorption: Following an oral administration, Cefadroxil gets rapidly absorbed from the gastrointestinal tract and is widely distributed in the body fluids and tissues. After a single administration of 500 mg or 1000 mg of Cefadroxil, average peak serum concentrations observed were around 16 and 28 mcg/mL (microgram per milliliter), respectively.
-
Distribution: About 20 percent of the drug is bound to plasma proteins. Measurable levels of the drug could be detected 12 hours after the administration.
-
Elimination: Approximately 90 percent of the drug was excreted unchanged in the urine within 24 hours. Following a single oral dose of 500 mg of Cefadroxil, peak urine concentration was around 1800 mcg/mL. It was observed that an increase in dosage produced a proportionate increase in the urinary concentration of Cefadroxil. The half-life of the drug is around one to two hours.
Drug Interactions of Cefadroxil
Some of the drugs which interact with Cefadroxil include;
-
Cholera vaccine.
-
BCG vaccine.
-
Typhoid vaccine.
-
Desogestrel.
-
Drospirenone.
-
Estradiol.
-
Ethinyl Estradiol.
-
Levonorgestrel.
-
Norgestrel.
-
Methotrexate.
-
Norethindrone.
-
Warfarin.
Clinical Studies
Clinical studies have demonstrated that Cefadroxil eradicated predominant pathogens such as Staphylococcus aureus, Streptococcus pneumoniae, beta-hemolytic Streptococci, Proteus mirabilis, and Escherichia coli. The safety and efficacy of Cefadroxil were evaluated in 1051 patients and 1030 patients, respectively. 91.8 percent clinical success was achieved, which resulted from a complete cure in 881 patients and 65 clinical cures. Success was observed in 97.5 percent and 84.5 percent of patients treated for respiratory and genito-urinary tract infections, respectively. However, side effects were reported in about 7.2 percent of the patients.
Non-clinical Toxicology
Long-term studies have yet to be performed with Cefadroxil to determine the carcinogenicity and mutagenicity. Reproduction studies conducted in rats and mice at doses up to 11 times the human dose have not demonstrated any evidence of impairment of fertility or fetal harm.
Specific Considerations
-
Pregnant Women: Adequate and well-controlled studies of Cefadroxil have not been conducted on pregnant women. Therefore, this drug must be used in pregnancy only if it is necessary.
-
Lactating Mothers: Studies have suggested that this drug poses minimal risk to the infant when taken during breastfeeding. Hence, caution is recommended.
-
Children: Various studies have been conducted, and no specific problems or issues have been demonstrated that would limit the use of Cefadroxil in children.
-
Elderly People: No significant differences have been identified between younger and elderly patients in treating urinary tract infections and skin infections during the clinical trials with Cefadroxil. For the treatment of tonsillitis or pharyngitis in patients above 65 years, a sufficient number were not included in the clinical studies. However, due to reduced renal function in elderly patients, care must be taken during dose determination and frequent monitoring must be performed.
-
Renal Impairment: As the kidneys excrete Cefadroxil, dose adjustment is required for patients with renal impairment.
