[Vocabulary] what's the opposite of "wear off" in this kind of sentence?

[dilodi83]

1) The wounded soldier was in great pain after the morphine wore off.
2) I guess the effect of the anaesthetic is going to wear off.
3) When I met John I fell for him immediately, but now it's been wearing off.

What's the opposite verb of "wear off" in these sentences where the verb means something like "to dimish"? Is there a particular phrasal verb to use or can the verb "to grow" be correct?

 

[Rover_KE]

An anaesthetic takes effect before it wears off.

In #3 there is nothing which can be said to be wearing off.

Feelings can grow (stronger), as you surmised.

Note spelling of diminish.

Rover

 

[Raymott]

1) The wounded soldier was in great pain after the morphine wore off.

The wounded soldier was in great pain until the morphine kicked in.

 

[Rover_KE]

The wounded soldier was in great pain until the morphine kicked in.

That's a great informal expression.

Rover

 

[Raymott]

That's a great informal expression.

Rover

Yes, it's more colloquial than "wear off", and couldn't be used in all situations as an antonym for "wear off".

 

[emsr2d2]

With regard to pain, you can say that a pain "came on" slowly, suddenly, over a couple of days etc.

As far as the anaesthetic is concerned, I would go with the colloquial "it's starting to kick in" first, then "it's starting to take effect".