COAMOX-MEPHA 457 SUSPENSION

Indications

• Bacterial infections of the respiratory tract, such as pneumonia and bronchitis
• Otitis media (middle ear infections)
• Sinusitis
• Skin and soft tissue infections
• Urinary tract infections
• Gonorrhea
• Helicobacter pylori eradication (as part of combination therapy for peptic ulcer disease)

Dosage

Children: Refer to the BNF for Children for appropriate dosing based on the child's age, weight, and clinical condition.

Adults: Refer to specific guidelines or the BNF for appropriate adult dosing based on the indication and severity of the infection.

Mechanism of action

Amoxicillin exerts its antibacterial effect by binding to penicillin-binding proteins (PBPs) located inside the bacterial cell wall. This binding inhibits the transpeptidation enzyme necessary for cross-linking peptidoglycan layers, ultimately disrupting cell wall synthesis and leading to cell death.

Pharmacodynamics

The pharmacodynamic properties of amoxicillin include its ability to exhibit time-dependent killing, with its efficacy linked to the time that serum concentrations remain above the minimum inhibitory concentration (MIC) for the target organism. Resistance can occur through the production of beta-lactamases, which hydrolyze the beta-lactam ring, rendering the antibiotic ineffective.

Pharmacokinetics

Amoxicillin is well absorbed from the gastrointestinal tract, with bioavailability ranging from 70% to 90%. It is widely distributed in body tissues and fluids, including the lungs, liver, and kidneys. Amoxicillin is minimally metabolized in the liver, with approximately 50-70% of the drug excreted unchanged in the urine. Its half-life is approximately 1 to 1.5 hours, necessitating multiple dosing to maintain effective plasma levels.

Contra-indications

• Hypersensitivity to penicillins
• History of severe allergic reactions to beta-lactam antibiotics

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Rash
• Allergic reactions
• Anaphylaxis
• Clostridium difficile-associated diarrhea

Interactions

• Probenecid may increase amoxicillin plasma levels
• Oral contraceptives may have reduced efficacy when used with amoxicillin
• Anticoagulants may have increased effects when used with amoxicillin

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of an allergic reaction
• Consider alternative therapy in patients with a history of gastrointestinal disease

Pregnancy

Amoxicillin is generally considered safe during pregnancy and is often used to treat infections in pregnant women.

Breast-feeding

Amoxicillin is excreted in breast milk, but is usually considered safe for use during breastfeeding.

Storage

Store at room temperature, away from moisture and heat. Reconstituted solutions should be refrigerated and used within a specified time frame.

Formulations

• Capsules
• Tablets
• Oral suspension
• Injection

Indications

• Infections caused by beta-lactamase-producing bacteria
• Acute bacterial sinusitis
• Acute otitis media
• Lower respiratory tract infections
• Urinary tract infections

Dosage

Children: Refer to the BNF for Children for specific dosing according to age and weight; adjustments may be necessary based on the clinical scenario.

Adults: Refer to specific product guidelines for dosing; typical regimens depend on the combination antibiotic used and the severity of the infection.

Mechanism of action

Clavulanic acid works by irreversibly binding to the active site of beta-lactamase enzymes that are produced by certain bacteria to inactivate beta-lactam antibiotics. By inhibiting these enzymes, clavulanic acid protects the penicillin antibiotic from degradation, allowing it to exert its antibacterial effects.

Pharmacodynamics

Clavulanic acid has a synergistic effect when combined with other antibiotics, particularly amoxicillin. The presence of clavulanic acid allows for the effective treatment of infections caused by bacteria that would otherwise be resistant to penicillins. Its antibacterial activity is generally weak on its own but significantly enhances the efficacy of other beta-lactam antibiotics.

Pharmacokinetics

Clavulanic acid is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 1 hour. It is widely distributed throughout the body and has a half-life of approximately 1 hour. The drug is primarily excreted unchanged in the urine. In the presence of renal impairment, dosage adjustment may be necessary, as the elimination of clavulanic acid can be affected.

Contra-indications

• Hypersensitivity to clavulanic acid or any of the excipients
• History of jaundice or hepatic impairment associated with previous use of penicillins or beta-lactam antibiotics

Adverse effects

• Nausea
• Diarrhea
• Rash
• Elevated liver enzymes
• Allergic reactions including anaphylaxis
• Superinfection

Interactions

• May enhance the effects of anticoagulants such as warfarin
• Probenecid may increase plasma concentrations of clavulanic acid
• May reduce the efficacy of oral contraceptives

Precautions

• Caution in patients with renal impairment
• Monitor liver function in patients receiving prolonged therapy
• Use with caution in patients with a history of allergic reactions to beta-lactams

Pregnancy

Clavulanic acid is categorized as pregnancy category B. Animal studies have not shown any harm to the fetus, but there are no adequate and well-controlled studies in pregnant women.

Breast-feeding

Clavulanic acid is excreted in breast milk, but it is generally considered safe for use during breastfeeding. Monitor for potential effects in the infant.

Storage

Store at room temperature, away from moisture and heat. Protect from light. Keep out of reach of children.

Formulations

• Oral tablets
• Oral suspension
• Injectable forms