After how long i am allowed to get pregnant if i do a treatment with antibiotics for an infection?

Depends...: Many antibiotics such as penicillin, Erythromycin, Zithromax and Augmentin (amoxicillin and clavulanate) are not known to harm a newly conceived pregnancy. Others, such as Doxycycline, Ciiprofloxacin Levofloxacin are usually avoided during pregnancy. Each antibiotic stays in your body a different length of time so the answer to your question depends on the antibiotic you are taking. Best wishes!