ALAMYCIN AEROSOL

Indications

• Bacterial infections
• Respiratory tract infections
• Urinary tract infections
• Acne vulgaris
• Rickettsial infections
• Chlamydia infections

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Oxytetracycline exerts its antibacterial effect by binding to the 30S ribosomal subunit of bacterial ribosomes. This binding inhibits the attachment of aminoacyl-tRNA to the mRNA-ribosome complex, thereby preventing the addition of new amino acids to the growing peptide chain and halting protein synthesis. This action is bacteriostatic, meaning it inhibits bacterial growth rather than directly killing the bacteria.

Pharmacodynamics

Oxytetracycline has a broad spectrum of activity and is effective against many common pathogens, including Staphylococcus aureus, Streptococcus pneumoniae, and Escherichia coli. It is particularly effective in treating infections in the respiratory and urinary tracts, as well as acne and certain skin infections. The drug's effectiveness is influenced by factors such as the site of infection, the susceptibility of the bacteria, and the presence of any resistance mechanisms.

Pharmacokinetics

Oxytetracycline is well absorbed from the gastrointestinal tract, with peak plasma concentrations typically occurring within 1 to 2 hours after oral administration. It has a bioavailability of approximately 60-80% when taken orally. The drug is widely distributed throughout the body and can penetrate into tissues, including bones and teeth. It is primarily excreted unchanged in the urine, and its half-life ranges from 6 to 12 hours, depending on dosage and individual metabolism.

Contra-indications

• Hypersensitivity to oxytetracycline or other tetracyclines
• Severe renal impairment
• Pregnancy (except in specific cases of severe infections where benefits outweigh risks)

Adverse effects

• Gastrointestinal disturbances including nausea, vomiting, and diarrhea
• Photosensitivity reactions
• Esophageal irritation or ulceration
• Hepatotoxicity
• Discoloration of teeth and inhibition of bone growth in children

Interactions

• Antacids and iron preparations may decrease the absorption of oxytetracycline
• Oral contraceptives may be less effective when taken with oxytetracycline
• Other antibiotics may have synergistic or antagonistic effects when used with oxytetracycline

Precautions

• Use with caution in patients with a history of liver disease
• Monitor for signs of superinfection during prolonged therapy
• Avoid use in children under 12 years unless absolutely necessary due to risk of tooth discoloration

Pregnancy

Oxytetracycline is contraindicated in pregnancy due to the risk of fetal harm, particularly dental and skeletal development.

Breast-feeding

Oxytetracycline is excreted in breast milk and may affect the growth of the infant; use with caution and consider alternative therapies.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Formulations

• Oral tablets
• Oral suspension
• Injectable form