You may suffer adverse effects from applying Vicks to your balls, so start with the lowest possible dosage. Extreme doses could be harmful. Menthol and eucalyptus are both safe in the doses present in Vicks. In fact, it is 30 times more permeable than regular skin, so if something gets on your balls, it’s likely to end up on your scrotum. Vicks contain menthol, which when applied to your balls will cause a painful cooling sensation. This is not recommended for application near your genitals.