indication

Oxytetracycline is indicated for treatment of infections caused by a variety of Gram positive and Gram negative microorganisms including Mycoplasma pneumoniae, Pasteurella pestis, Escherichia coli, Haemophilus influenzae (respiratory infections), and Diplococcus pneumoniae.

pharmacology

Oxytetracycline is known as a broad-spectrum antibiotic due to its activity against such a wide range of infections. It was the second of the tetracyclines to be discovered. Oxytetracycline, like other tetracyclines, is used to treat many infections common and rare. Its better absorption profile makes it preferable to tetracycline for moderately severe acne, but alternatives sould be sought if no improvement occurs by 3 months.

mechanism of action

Oxytetracycline inhibits cell growth by inhibiting translation. It binds to the 30S ribosomal subunit and prevents the amino-acyl tRNA from binding to the A site of the ribosome. The binding is reversible in nature. Oxytetracycline is lipophilic and can easily pass through the cell membrane or passively diffuses through porin channels in the bacterial membrane.

toxicity

Adverse effects may include stomach or bowel upsets and rarely allergic reactions. Very rarely severe headache and vision problems may be signs of dangerous intracranial hypertenion.

absorption

Readily absorbed following oral administration.

drug interactions

Acitretin: Increased risk of intracranial hypertension

Amoxicillin: Possible antagonism of action

Ampicillin: Possible antagonism of action

Calcium: Formation of non-absorbable complexes

Carbenicillin: Possible antagonism of action

Clavulanate: Possible antagonism of action

Cloxacillin: Possible antagonism of action

Dicloxacillin: Possible antagonism of action

Ethinyl Estradiol: This anti-infectious agent could decrease the effect of the oral contraceptive

Etretinate: Increased risk of intracranial hypertension

Flucloxacillin: Possible antagonism of action

Iron Dextran: Formation of non-absorbable complexes

Isotretinoin: Increased risk of intracranial hypertension

Magnesium: Formation of non-absorbable complexes

Penicillin G: Possible antagonism of action

Penicillin V: Possible antagonism of action

Piperacillin: Possible antagonism of action

Pivampicillin: Possible antagonism of action

Pivmecillinam: Possible antagonism of action

Ticarcillin: Oxytetracycline may reduce the effect of Ticarcillin by inhibiting bacterial growth. Ticarcillin exerts its effects on actively growing bacteria. To achieve synergism, Ticarcillin should be administered at least 2 hours prior to using Oxytetracycline.

Tretinoin: Oxytetracycline may increase the adverse effects of oral Tretinoin. Increase risk of pseudotumour cerebri. Concurrent therapy should be avoided.