Side effects

As with antibiotics administered in tablet form, eye drops containing antibiotics also always carry the risk of an allergic reaction. Furthermore, prolonged use can lead to damage of the cornea with ulcerations. In principle, many antibiotics are well tolerated by alcohol, which is why an absolute ban on alcohol is not necessary.

These include antibiotics used for eye diseases, e.g. gentamycin, tetracycline, doxycycline and ofloxacin. Since antibiotics in ophthalmology are usually administered locally, i.e. in the form of drops or ointments, the effect of antibiotics on the body is also much less pronounced than with a tablet or an infusion. The incoming dose and thus also the interaction of the antibiotic with alcohol is therefore much lower and actually negligible.

Despite everything, however, you should know that not all antibiotics are compatible with alcohol. Antibiotics such as metronidazole or tinidazole, for example, inhibit the complete breakdown of alcohol by inhibiting an important enzyme that breaks down alcohol into harmless acetate. By inhibiting the enzyme, it can lead to severe symptoms of poisoning such as nausea, vomiting, headaches, shortness of breath and cardiac arrhythmia.

This is also known as the “antabuse effect”. In order to avoid this complication, it is advisable to refrain from drinking alcohol during and until 3 days after the end of therapy with metronidazole. Patients with known liver or kidney disorders are also not allowed to drink alcohol while taking antibiotics, as this would result in life-threatening complications.

As a precaution, this should also be taken into account when taking antibiotic-containing eye drops. Since antibiotics in ophthalmology are usually applied locally in the form of drops, the effect of antibiotics on the body is very small. As a result, there is usually no interaction with the pill, which is why the effectiveness of the pill is NOT negated when antibiotic-containing eye drops are used.

However, if, for example, any interaction with the pill or effects on the bowel (diarrhoea) are described in the package insert of the antibiotic, pregnancy may become possible and additional contraception with a condom should be used during and up to 7 days after the end of antibiotic therapy. If the antibiotic is only taken during the pill break, no additional contraception is necessary. Gentamycin, neomycin and kanamycin have usually also been taken as tablets, have no interaction with the pill and can therefore be taken without any danger in principle.

Drops containing antibiotics during pregnancy

During pregnancy, antibiotic-containing eye drops should be used with caution and only if necessary. Antibiotics such as gentamycin, kanamycin and neomycin may be used in the form of eye drops or eye ointments, as these are only absorbed into the body’s circulation to a small extent and therefore have little or no effect on the maternal circulation. Antibiotics such as tetracycline or doxycycline can cause liver damage during pregnancy and should in principle not be prescribed.

Ciprofloxacin should also not be used in the form of eye drops, as there are only a few studies that confirm that it is safe. During the breastfeeding period, many medications must be questioned as to whether they can be taken despite breastfeeding. The question is always whether the active substance can be transferred from the nursing mother to the child.

If this is the case, the child should not be breastfed during the time the medication is taken. It may also be possible to take another drug with the same or a comparable mode of action which does not pass into breast milk and therefore cannot be passed on to the breastfed child. Many eye drops are designed in such a way that the antibiotic they contain only works locally on the eye and little or no of the active ingredient is absorbed into the body and bloodstream.

Therefore, the antibiotic-containing eye drops can usually be taken during breastfeeding. However, since there are differences in composition and effectiveness regardless of the active ingredient and the manufacturer, a doctor should always be consulted before taking antibiotic-containing eye drops. In most cases, a note on pregnancy and breastfeeding can be found in the package insert of antibiotic-containing eye drops.