Synonyms for Have second thoughts:

• v.

  •back-pedal (verb)
  • renege,
  • do a u-turn,
  • take back.
  •reconsider (verb)
  • polish,
  • rework,
  • emend,
  • go over,
  • rearrange,
  • correct,
  • rehash,
  • retrace,
  • reexamine,
  • amend,
  • run through,
  • revise.
  •reevaluate (verb)
  • re evaluate,
  • re-evaluates,
  • re evaluated,
  • re evaluates,
  • re evaluating.
  •rethink (verb)
  • re thinking,
  • re thinks,
  • re-thinking,
  • re thought,
  • re think,
  • re-think,
  • re-thinks,
  • re-thought.

• Other synonyms:

  •reevaluate
  • re-evaluate,
  • re-evaluating,
  • re-evaluated.
  •Other relevant words:
  • come round,
  • review,
  • rethink,
  • wheel,
  • tergiversate,
  • backpedal.

Antonyms for Have second thoughts:

• v.

  • reconsider
    ignore, spoil, refuse.