demeclocycline hydrochloride at a glance
Medicine class
Tetracycline antibiotic.
Other licensed role
Selected cases of chronic hyponatraemia caused by SIADH associated with malignant disease.
Taking the capsules
Swallow whole with plenty of water while sitting or standing; food, milk and several minerals reduce absorption.
Sun sensitivity
Minimise exposure to sunlight and sunlamps; seek advice if skin discomfort develops.
What is demeclocycline hydrochloride used for?
The selected product is licensed for:
Infections caused by organisms susceptible to tetracyclines, including specified uncommon infections.
Severe acne vulgaris.
Chronic hyponatraemia due to SIADH secondary to malignant disease when water restriction is ineffective and cirrhosis is absent.
How does demeclocycline hydrochloride work?
For infection, it disrupts bacterial protein production and prevents susceptible bacteria from growing. In SIADH, it reduces the kidney’s response to vasopressin, promoting more dilute urine; the response varies.
demeclocycline hydrochloride preparations and strengths
Capsule
Route: Oral
Strengths: 150 mg, 300 mg
How to take demeclocycline hydrochloride
Follow the prescription label. Do not alter or stop treatment without discussing it with the prescriber, particularly when it controls SIADH.
Swallow capsules whole with plenty of water while sitting or standing.
Do not take immediately before lying down because tetracyclines can injure the oesophagus.
Take on an empty stomach as directed; food, milk and dairy products impair absorption.
Do not take alongside antacids or products containing iron, calcium, zinc, magnesium or aluminium; ask a pharmacist how to separate them.
demeclocycline hydrochloride side effects
Common or expected effects
- Nausea, vomiting, diarrhoea or stomach upset
- Heartburn or irritation of the gullet
- Headache or dizziness
- Thrush
- Increased sensitivity to sunlight
- Rash or itching
Get urgent medical advice
- Severe allergic reaction, including wheezing or facial swelling
- Blistering, peeling or widespread severe skin reaction
- Persistent severe headache or blurred vision
- Severe watery diarrhoea or marked abdominal pain
- Signs of liver injury, such as yellow skin or eyes or dark urine
- Markedly changed urination, intense thirst or difficulty passing urine
- Unusual bruising, mouth ulcers or persistent sore throat
demeclocycline hydrochloride in pregnancy
The selected product is contraindicated during pregnancy. Tetracyclines cross the placenta, and later exposure may affect developing teeth and bone. Contact the prescriber promptly if pregnancy occurs or is planned.
demeclocycline hydrochloride while breastfeeding
The selected product is contraindicated while breastfeeding. Specialist guidance says cautious use may sometimes be considered for a full-term, healthy infant with monitoring, but evidence is limited and prolonged or repeated exposure is generally avoided. Individual professional assessment is required.
demeclocycline hydrochloride interactions
Check all prescribed, over-the-counter and complementary products with a pharmacist or prescriber. Important examples include:
Antacids and iron, calcium, zinc, magnesium or aluminium products
They bind demeclocycline in the gut and reduce absorption, so they should not be taken together.
Milk, dairy products and food
They can reduce absorption.
Warfarin, coumarins and phenindione
The anticoagulant effect may increase, requiring closer clotting surveillance and possible adjustment.
Common questions about demeclocycline hydrochloride
Answers are fully visible for fast scanning and source review.
What is demeclocycline hydrochloride used for?
It treats susceptible bacterial infections and severe acne. It also has a restricted licence for chronic hyponatraemia caused by SIADH associated with malignant disease.
Why is it used for SIADH?
It reduces the kidney’s response to vasopressin, allowing more free water to be excreted. Its effect varies, so biochemical and renal monitoring are important.
Can it be taken with food or milk?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.