5-FU injection and topical even in small doses cause both acute central nervous system (CNS) damage and progressively worsening delayed degeneration of the CNS in mice. This latter effect is caused by 5-FU-induced damage to the oligodendrocytes that produce the insulating myelin sheaths.
Home > Sexually transmitted infections > Syphilis > After treatment for syphilis. It is strongly advised that you do not have any sexual intercourse; including vaginal; anal or oral sex until you and your partner(s) have both finished the treatment and any follow-up treatment.
How soon after sex can I have a check-up? It is important not to delay going for a check-up if you think you might have chlamydia. A test can be carried out straightaway but you may be advised to have another test two weeks after having sex. You can have a test for chlamydia even if there are no symptoms.