Mode of action and areas of application | Amoxicillin and alcohol – is that compatible?

Mode of action and areas of application

Amoxicillin is a drug that belongs to the group of antibiotics. Antibiotics have an antimicrobial effect and are therefore used to treat infections. However, an antibiotic is only effective against infectious diseases caused by bacteria.

Their use against viral infections is therefore ineffective. Amoxicillin belongs to the group of so-called penicillins. Penicillins have an antibiotic effect by inhibiting the formation of the bacterial cell wall during the growth phase.

In doing so they block the so-called penicillin-binding proteins. Penicillins are particularly effective against so-called gram-positive bacteria. Gram-positive or gram-negative only describes the ability of the bacteria to be stained with a specific dye.

Such gram-positive bacteria are, for example, streptococci, which can cause tonsillitis or even erysipelas. In contrast to classical penicillin, amoxicillin has a broader spectrum of activity with an additional effect against so-called gram-negative bacteria such as E. coli, so that it can also be used in the treatment of urinary tract infections. Amoxicillin can therefore be used against both acute and chronic bacterial infections, which lie within the spectrum of action of Amoxicillin and can be achieved by oral administration of medication. Classical areas of application are therefore infections of the ear, nose and throat area such as tonsillitis, middle ear infections or sinusitis. Amoxicillin is also very well suited as part of a triple therapy against Helicobacter pylori in the case of gastritis or for endocarditis prophylaxis.


For the use of amoxicillin, some special warnings apply which must be observed. In case of known hypersensitivity to the active substance Amoxicillin or any other penicillin, it is strictly forbidden to take Amoxicillin, as taking it can lead to severe and life-threatening allergic reactions. It is particularly important to ask about previous treatments with penicillins, cephalosporins, other beta-lactam antibiotics and their tolerability. This is because so-called cross-allergies with other beta-lactam antibiotics such as cephalosporins can occur. In addition, patients with previously known allergies or allergic asthma have a higher risk of suffering an allergic reaction due to treatment with amoxicillin.

Side effects

As with all drugs, there are numerous side effects and interactions known under amoxicillin therapy. Amoxicillin therapy requires increased vigilance in case of a simultaneous viral infection. In particular in cases of simultaneous infectious mononucleosis (Pfeiffer’s glandular fever) or lymphatic leukaemia, Amoxicillin should not be used for antibacterial therapy at all or only with great caution, since the risk of a skin reaction increases significantly with the administration of Amoxicillin.

Likewise, limited kidney function makes it necessary to adjust the dosage of Amoxicillin. In this case, a restriction of the kidney function can lead to an accumulation of amoxicillin in the body. This can lead to seizures, impaired blood clotting and reduced uric acid excretion.

These side effects can be critically increased by alcohol in particular. However, treatment with amoxicillin itself can also damage a previously healthy kidney to such an extent that kidney failure occurs. The gastrointestinal tract is very often a place where side effects of amoxicillin therapy become noticeable.

As with almost all antibiotics, taking them can lead to nausea, vomiting and diarrhoea. Occasionally, this may be so-called pseudomembranous colitis, which requires immediate discontinuation of antibiotic administration and requires simultaneous treatment of this side effect. A colitis is an inflammation of the colon.