Presented by – Maniz JoshiB.Pharmacy 8th sem

HOPE International College Satdobato, Lalitpur, Nepal.

Adverse Drug Reactions of Tetracycline Antibiotics

IntroductionTetracyclines are a class of antibiotics having a

nucleus of four cyclic rings.They were discovered in the 1940s, are a family of

antibiotics that inhibit protein synthesis by preventing the attachment of aminoacyl-tRNA to the ribosomal acceptor (A) site. Tetracyclines are broad-spectrum agents, exhibiting activity against a wide range of gram-positive and gram-negative bacteria, atypical organisms such as chlamydiae, mycoplasmas, and rickettsiae, and protozoan parasites. 

Tetracycline has been assigned to pregnancy category D by the FDA.

Irritative effectsTetracyclines have irritant property, can

cause:a) Epigastric pain b) Nausea and vomiting

c) Diarrhoea

Note* Odynophagia and esophageal ulceration has been reported due to the release of the material from capsules in the esophagus during swallowing, specially with Doxycycline.

Liver Damage

Fatty infiltration of liver and jaundice occurs occassionally. Oxytetracycline and tetracycline are safer in this regard. Tetracyclines are risky in pregnant women; can precipitate acute hepatic necrosis which may be fatal.

Kidney damage

It is a risk only in the presence of existing kidney disease.

All tetracyclines, except doxycycline, accumulate and enhance renal failure.

A reversible fanconi syndrome like condition is produced by outdated tetracyclines. This is caused by degraded products – epitetracycline, anhydrotetracycline and epianhydrotetracycline.

Phototoxicity

A sunburn-like or other severe skin reaction on exposed parts is seen in some individuals.

The relative scale of toxicity magnification ranges from the most to the least toxic is: doxycycline > chlortetracycline > demeclocycline > tetracycline.

Minocycline is the least phototoxic.

Teeth and bones

Tetracyclines have chelating property. Calcium-tetracycline chelate gets deposited in developing teeth and bone.

Given during late pregnancy or childhood, tetracyclines can cause temporary suppression of bone growth and permanent tooth staining.

The period of greatest danger is from mid pregnancy to about 4 to 6 months of the postnatal period for the deciduous anterior teeth, and from a few months to 5 years of age for the permanent anterior teeth

Tetracyclines are not recommended for treatment in children younger than 8 years of age.

BNF C 2006 lists tetracycline, demeclocycline, doxycycline, lymecycline,minocycline and oxytetracycline for use in children above 12 yrs.

Others1) Anti anabolic effectTetracyclines reduce protein synthesis and have an overall catabolic effect.They induce negative nitrogen balance and can increase blood urea.2) Increased intracranial pressure is noted in some infants.3) Diabetes InsipidusDemeclocycline antagonizes ADH action and reduces urine concentrating ability of the kidney.4) Vestibular toxicityMinocycline can cause ataxia, vertigo and nystagmus, which subside when the drug is discontinued.

ReferenceEssentials of Medical pharmacology by K.D

tripathi 7th EditionSecond Meeting of the Subcommittee

of the Expert Committee on the Selection and Use of Essential Medicines Geneva, 29 September to 3 October 2008

http://www.hindawi.com/journals/atox/2015/787129/

http://www.drugs.com/pregnancy/tetracycline.html

Thank You!Any Query??