What is Doxycycline?

Doxycycline is a prescription-only antibiotic from the tetracycline family. It is widely used in the UK to treat specific bacterial infections—including acne, rosacea and chlamydia—and is also an established option for preventing malaria in travellers visiting risk areas.

It works by stopping bacteria and malaria parasites from making the proteins they need to grow. Doxycycline is usually taken once a day and comes as capsules or tablets.

What is Doxycycline Used For?

Malaria Prevention: Taken daily to help prevent malaria when visiting areas where the disease is common and resistant to other medicines.

Bacterial Infections: Doxycycline is also prescribed for conditions such as acne, rosacea, and certain sexually transmitted infections (for example, chlamydia). Further details for these uses are provided on the relevant treatment pages on our website.

Note: At 123Meds we supply doxycycline only for malaria prevention or for the specific infections listed above. For any other condition, please speak with your GP or a qualified prescriber.

How Doxycycline Works

Doxycycline stops bacteria and some parasites from multiplying in the body.

Mechanism of Action

Blocks Protein Production: Prevents bacteria from making the proteins they need to survive.
Stops Malaria Parasite Growth: When used for malaria prevention, it prevents the parasite from multiplying in the blood, reducing the chance of illness while travelling.

Malaria Prevention

Doxycycline is used to prevent, not treat, malaria.
Travellers should begin the medicine 1–2 days before entering a malaria-risk area, continue daily while there, and keep taking it for four weeks after leaving to ensure full protection.
If you develop symptoms such as fever, chills, or headaches during or after travel, seek urgent medical attention—diagnosis and treatment of malaria require specialist care.

Can Doxycycline 100 mg Capsules Be Purchased Over the Counter?

No. Doxycycline is a Prescription-Only Medicine (POM) in the UK.
You need a valid prescription from a registered prescriber, but you can obtain it through an online consultation with a UK-registered clinician who will confirm the correct use for malaria prevention or approved infections.

Alternative Antimalarial Medications

Other options include:

Atovaquone/Proguanil: Daily tablet, start 1–2 days before travel and continue 7 days after return.
Mefloquine: Weekly dose, begin 2–3 weeks before travel and continue 4 weeks after return.

Your prescriber will advise which is most suitable based on your destination, health, and tolerance.

Directions: How to Take Doxycycline

Timing & Dose: Adults - take one 100 mg capsule once daily.

Start 1–2 days before entering a malaria-risk area, continue each day during travel, and keep taking it for 4 weeks after leaving.

How to Take: Swallow the capsule whole with a full glass of water. Remain upright for at least 30 minutes to avoid throat irritation.

With Food: Can be taken with food or a milky drink to reduce stomach upset. Avoid dairy or calcium-rich foods within 2 hours of your dose.

Missed Dose: Take as soon as you remember unless it’s almost time for the next dose. Do not double up.

Active Ingredient: Doxycycline hyclate.

Inactive Ingredients: May include lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

Dr Reddy's Laboratories, Morningside Healthcare, Meda Pharmaceuticals, Dexcel Pharma, and other licensed UK pharmaceutical companies

Most people tolerate doxycycline well, but side effects can occur.

Common Side-Effects

Stomach upset, nausea, diarrhoea
Headache
Skin sensitivity to sunlight
Mild abdominal pain or cramps
Sore throat or irritation if not swallowed properly
Occasional vomiting or oral/vaginal thrush

Less Common but Serious – Seek Urgent Help (GP, NHS 111 or A&E)

Signs of a severe allergic reaction: swelling of the face/lips/tongue, difficulty breathing, rash or hives
Yellowing of the skin or eyes (possible liver problems)

Severe or persistent diarrhoea with stomach pain (may indicate colitis)

Safety Advice:

• Protect your skin from sunlight with high-SPF sunscreen and clothing.
• Drink plenty of water and remain upright after taking each capsule.
• If you develop any sudden rash, breathing difficulty, severe abdominal pain, or persistent vomiting, stop the medication and seek emergency medical care.