Demeclocycline hydrochloride

An antibiotic used in the treatment of bacterial infections

Demeclocycline hydrochloride is a broad-spectrum antibiotic belonging to the tetracycline class. It is primarily used in the treatment of bacterial infections and is known for its ability to inhibit protein synthesis in bacteria, thereby preventing their growth and proliferation.

Mechanism of Action

Demeclocycline works by binding to the 30S ribosomal subunit of bacteria, inhibiting the attachment of aminoacyl-tRNA to the mRNA-ribosome complex. This action effectively halts bacterial protein synthesis, which is essential for bacterial growth and replication. As a result, demeclocycline exhibits bacteriostatic activity, meaning it stops bacteria from multiplying but does not necessarily kill them outright.

Clinical Uses

Demeclocycline is used to treat a variety of infections caused by susceptible strains of bacteria. These include:

• Respiratory tract infections
• Urinary tract infections
• Skin and soft tissue infections
• Acne vulgaris

Additionally, demeclocycline has a unique application in the treatment of SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion), where it helps to correct hyponatremia by inducing nephrogenic diabetes insipidus.

Pharmacokinetics

Demeclocycline is administered orally and has a bioavailability of 60–80%. It is moderately bound to plasma proteins (41–90%) and is metabolized in the liver. The elimination half-life of demeclocycline is approximately 10–16 hours, and it is primarily excreted via the kidneys.

Adverse Effects

Common side effects of demeclocycline include:

• Gastrointestinal disturbances such as nausea, vomiting, and diarrhea
• Photosensitivity, leading to an increased risk of sunburn
• Discoloration of teeth in children

Serious adverse effects may include:

• Hepatotoxicity
• Renal impairment
• Hypersensitivity reactions

Contraindications

Demeclocycline is contraindicated in:

• Pregnant women (Pregnancy Category D)
• Children under the age of 8 years due to the risk of permanent tooth discoloration
• Patients with known hypersensitivity to tetracyclines

Also see

• Tetracycline antibiotics
• Antibiotic resistance
• Protein synthesis inhibitors
• Syndrome of inappropriate antidiuretic hormone secretion

List of tetracyclines

• Demeclocycline
• Doxycycline
• Minocycline
• Tetracycline
• Tigecycline