How azithromycin works
Among other things, the human immune system protects the body against the implantation and spread of invaders such as bacteria and viruses. As soon as such a pathogen finds its way into the organism, the immune system reacts immediately and fights it with various mechanisms.
As a rule, the person concerned does not even notice this, or only mild symptoms occur as a result of the increased activity of the immune system or the infectious agent. Sometimes, however, the body’s defenses do not immediately manage to successfully fight the pathogens – the symptoms of the disease then become more severe. In such cases, the body’s defense can be supported with medication.
Absorption, degradation and excretion
Azithromycin is incompletely absorbed (approximately 40 percent) from the intestine into the blood after ingestion by mouth. Degradation takes place in the liver. The breakdown products are excreted via the kidneys (i.e., with the urine) and via the intestines (with the stool).
When is azithromycin used?
The active ingredient azithromycin is used for various clinical pictures (indications) when they are caused by appropriately sensitive bacteria. These include:
- Infections of the upper respiratory tract (e.g., sinusitis, tonsillitis)
- Lower respiratory tract infections (e.g., bronchitis, pneumonia)
- skin and soft tissue infections
- acute otitis media
- certain genital infections (e.g. chlamydia)
How azithromycin is used
The total dose of azithromycin for respiratory infections, middle ear infections, and skin and soft tissue infections is 1.5 grams. These are usually taken according to the schedule of a 3-day therapy: Here, 500 milligrams of azithromycin are taken once daily for three days each.
For genital infections, the total dose is only one gram, which can be taken all at once.
For patients weighing less than 45 kilograms, the azithromycin dosage is reduced.
What are the side effects of azithromycin?
Very often (in more than ten percent of those treated), the therapy causes gastrointestinal symptoms. Frequently, i.e. in one to ten percent of those treated, azithromycin causes side effects such as headache, dizziness, skin rash and visual disturbances.
Even more rarely, photosensitivity, liver dysfunction, kidney dysfunction, discoloration of the teeth, and hearing disorders occur.
What should be considered when taking azithromycin?
Azithromycin should be used with caution in liver dysfunction, as the active substance is broken down by the liver. The same applies if blood salt levels are too low (especially in case of potassium and magnesium deficiency) and in case of certain heart problems (QT interval prolongation, severe heart dysfunction, too slow heartbeat = bradycardia).
Drug interactions
If several medicines are taken at the same time, they can influence each other’s effects. For example, the following agents increase the side effects of azithromycin when used at the same time:
- Ergot alkaloids (used in migraine, circulatory disorders, hypertension, and Parkinson’s disease).
- astemizole (for allergies)
- alfentanil (for pain relief during surgery)
Conversely, azithromycin increases the effect of the following drugs:
- digoxin (for heart dysfunction)
- ciclosporin (immunosuppressant)
- Colchicine (e.g. for gout)
Trafficability and operation of machines
Reactivity is not affected by taking azithromycin. However, side effects such as dizziness and convulsions may occur.
Therefore, at the beginning of treatment, a patient should monitor his or her individual response to the drug before actively participating in traffic or operating heavy machinery.
Age Limitation
Azithromycin may be administered from birth if indicated. In children and adolescents with a body weight up to 45 kilograms, the dosage is administered individually in accordance with the body weight.
Pregnancy and lactation
Azithromycin may be used during pregnancy and lactation.
The level of experience with the use of azithromycin during pregnancy is high. It has been shown that the active substance has no harmful effect on the unborn child.
How to obtain medicines containing azithromycin
Azithromycin is subject to prescription in Germany, Austria and Switzerland and is only available from pharmacies with a prescription from a doctor. Eye drops containing azithromycin are on sale in Germany and Austria, but not in Switzerland.