Introduction

Name

• Oxytetracycline.

Class of drug

• Tetracycline antibiotic.

Description

Chemical name

• [4S-(4-alpha,4a-alpha,5-alpha,5a-alpha,6-beta,12a-alpha)]-4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,5,6,10,12,12a-hexahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide.

Molecular formula

• C22H24N2O9.

Physical properties

• Aqueous solution.
• Tablets.

Storage requirements

• <25°C.
• Protect from light.

Uses

Indications

• Inhibits the growth of many gram-positive and gram-negative bacteria, rickettsiae, mycoplasma, spirochetes and other microbes.

Administration

Pharmacokinetics

Precautions

Interactions

with other drugs

Penicillins

• The bactericidal action of the penicillins may be inhibited by oxytetracycline.

Drugs decreasing absorption by binding to tetracycline

• Antacids containing divalent or trivalent cations (Mg, Ca, Al).
• Iron.
• Sodium bicarbonate.

Digoxin

• The availability may be increased by tetracyclines for months after their discontinuation leading to digoxin toxicity.

Anticoagulants

• Plasma prothrombin activity may be reduced by tetracyclines and therefore patients on anticoagulant therapy may need a dose adjustment.

Methoxyflurane

• Tetracyclines may increase the nephrotoxic effects.

Theophyllines

• The GI effects of tetracyclines may be increased.

Adverse Reactions

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• McGrotty Y L & Knottenbelt C M (2002) Oesophageal stricture in a cat due to oral administration of tetracyclines. J Small Anim Pract 43 (5), 221-223.
• Watson A D (1992) Bioavailability and bioinequivalence of drug formulations in small animals. J Vet Pharmacol Ther 15 (2), 151-159.
• Riond J L, Vaden S L & Riviere J E (1990) Comparative pharmacokinetics of doxycycline in cats and dogs. J Vet Pharmacol Ther 13 (4), 415-424.
• Schwarz S, Roberts M C, Werckenthin C, Pang Y & Lange C (1998) Tetracycline resistance in Staphylococcus spp. from domestic animals. Vet Microbiol 63 (2-4), 217-227.

Other sources of information

• Ramsey I (2017) BSAVA Small Animal Formulary. 9th edn.
• Based on Small Animal Formulary. Tennant B (1999) 3rd edn. BSAVA, UK. ISBN: 0 9052 1452 8.