Can chewing cloves often have bad or harmful side effects?

No, know limit: As long 1/ day its ok as its very acidic every yhing good in limit.

Not usually but: Repeated, frequent applications in your mouth or on your gums can lead to damage to teeth ; gums. Clove should be stopped at least 2 weeks before surgeries because it contains eugenol which can slow blood clotting. It may be contraindicated with some bleeding disorders. Oral use of clove oil can be unsafe for children.