Azithromycin is a very potent antibiotic based on the active ingredient of the same name. Originally developed and marketed in the early 1990s by Pfizer under the brand name Zithromax, this medicine is used ever since for the treatment of a wide range of bacterial infections, including chlamydia. Azithromycin found today is a generic medicine that is produced by a number of different pharmaceutical companies for years now – ever since the expiration of the original patent that was owned by Pfizer.

Generic drugs are those medicines that rely on the same active ingredient as so-called “original” branded medicines. In order to be legally sold on the modern markets, they need to prove bioequivalence with the original, meaning they have the same active ingredient, are used for the treatment of the same conditions in the same dose and with the same possible side effects.

What’s on this page:

What is chlamydia?

Chlamydia is undoubtedly the most common sexually transmitted condition in the UK with more than 200.000 new cases being reported to GUM and STI clinics every year. Although this condition can affect anyone who is sexually active, chlamydia is significantly more common in young people, aged 18 to 24 as compared to other age groups, and the prevalence is also significantly greater in women, as compared to men.

What makes chlamydia especially difficult to diagnose early on is the fact that it can produce absolutely no symptoms for long periods of time. In fact, as much as 50% of all men affected and 80% of women affected show absolutely no signs of infection, making it very hard to notice that something is wrong prior to symptoms manifesting – that is, unless you undergo regular STI testing which is the best precaution for all sexually active individuals.

Once symptoms do manifest, they can are pretty unspecific, making it hard to pinpoint the exact nature of the issue without a proper STI test. Women may experience painful urination, increased menstrual bleeding or changes in vaginal discharge, while man will notice penile discharge, urinary pain and pain in testicles.

If left untreated, even when asymptomatic, the condition can cause significant complications, most notably, pelvic inflammatory disease in women and infertility in both sexes.

How Azithromycin treats chlamydia?

Azithromycin based on the active ingredient of the same name is scientifically classified as a macrolide antibiotic. This means that it treats bacterial infections by directly affecting the bacterial cells which are the root cause of the infection. More specifically, azithromycin will disrupt some of the vital cellular processes, including the synthesis and production of a specific protein enzyme that plays a crucial role in the multiplication of the bacteria. With the production of this compound inhibited by the activity of the medicine, bacteria can no longer increase in number, becoming vulnerable to body’s natural defences that will then proceed to eliminate the infection from the body entirely.

For the treatment of bacterial STIs and urethral infections, just a one-off dose of Azithromycin will be enough to turn the tide and help the immune system fend of the bacteria.

Can I buy chlamydia treatment online?

If you have any reason to suspect you might be infected by chlamydia (or any other STI), you should immediately seek medical attention and subsequent STI testing. You can accomplish this either by making and appointment with your general practitioner or visiting a local GUM or STI clinic. Alternatively, if you would prefer to avoid talking to someone face-to-face about your sexual health, you might be interested in ordering an at-home STI testing kit. This kit can be used in the comfort of your home to gather urine samples and vaginal swabs in a do-it-yourself manner. Later, you will send the samples to a certified laboratory which will inform about the results via communication channel of your choosing.

If you are tested positive, there are, again, two options. You can make yet another appointment with your doctor, ask for a prescription and then wait in line in a pharmacy or, alternatively, you can contact an online clinic of your choice where the doctor will use an online customized questionnaire and the results of your test in order to determine whether you are suitable for the treatment. If the prescription is issued, it will be automatically used to send the required medicine straight to your doorstep.

How to use Azithromycin?

Using Azithromycin is very simple – you just need to follow instructions that will be provided both by your doctor and in the official patient information leaflet that is issued with every pack of the medicine. The most general guidelines can be described as follows:

  • Take the medicine as prescribed
  • For chlamydia, standard dose is 1000mg (two tablets of 500mg)
  • Ensure you take the tablets whole (do not chew or break them up)
  • Take the tablets with water
  • Never use more than the prescribed amount

What are Azithromycin side effects?

Just like majority of antibiotics, Azithromycin is very safe and reliable when it comes to side effects. Despite the fact that adverse effects will manifest only in a fraction of those using it, it is still important to get familiar with what could go wrong, so you can notice the side effects early on and ask for medical attention if needed.

Frequency of occurrence

Side effects

Very Common (1 in 10 users or more)

Pain in the abdomen, diarrhoea, feeling sick


Common (1 in 10 users or less)

Loss of appetite, dizziness, headache, sight or hearing problems, indigestion, joint pain

Uncommon (1 in 100 users or less)

Fungal or bacterial infections, chest pain, loss of breath, gastroenteritis, vaginitis, pneumonia, drowsiness, allergic skin reaction

Rare (1 in 1000 users or less)

Agitation, kidney problems


Are there any Azithromycin interactions to be aware of?

Yes, Azithromycin is known to adversely interact with the following medicines:

  • Ergotamine
  • Statins
  • Quinidine
  • Warfarin
  • Nelfinavir
  • Rifabutin
  • Alfentanil
  • Antacids
  • Digoxin
  • Astemizol
  • Pimozide

Azithromycin contraindications

There are some cases when Azithromycin might not be recommended. This can be the case if you are affected by any of the following conditions:

  • Diabetes
  • Liver or kidney problems
  • Bowel disease
  • Severe heart problems
  • Neurological and psychiatric illnesses
  • Allergy to antibiotics
  • Nut allergy
  • Lactose intolerance

It is also important to note that this medicine shouldn’t be used during pregnancy or if you are currently breastfeeding unless it is absolutely necessary. In addition to that, it is also vital that you don’t consume alcohol 48 hours before and 48 hours after taking Azithromycin.