the boby temperature drops

[ostap77]

If I'm running a high temperature and the doctor gives me a remedy so the temperature eventualy drops down.

Can we say " I'll give him some antibiotics to drop down the temperature."?

[Raymott]

If I'm running a high temperature and the doctor gives me a remedy so the temperature eventualy drops down.

Can we say " I'll give him some antibiotics to drop down the temperature."?

You can say it grammatically, but it's incorrect. Antibiotics are not antipyretic. If the fever is caused by a bacterial infection, the antibiotics are given to kill the bacteria. Once this has happened, the temperature will go down by itself. In the absence of bacteria to kill, antibiotics will not affect your temperature.
However, you can say, "I'll take some paracetamol (acetaminophen) - or aspirin, or ibuprofen - to bring down my temperature; or I'll take a cool bath to lower my temperature.

[ostap77]

You can say it grammatically, but it's incorrect. Antibiotics are not antipyretic. If the fever is caused by a bacterial infection, the antibiotics are given to kill the bacteria. Once this has happened, the temperature will go down by itself. In the absence of bacteria to kill, antibiotics will not affect your temperature.
However, you can say, "I'll take some paracetamol (acetaminophen) - or aspirin, or ibuprofen - to bring down my temperature; or I'll take a cool bath to lower my temperature.

Can we say "drop his temperature"?

[Raymott]

Can we say "drop his temperature"?

You can.
We need to drop his temperature.
We need to get his temperature down.
We need to bring down his fever. (This might be a local variation)

You'll be understood whatever you say.

[susiedqq]

How about:

I'll give him some medicine to lower his temperature.

[sato]

If I'm running a high temperature and the doctor gives me a remedy so the temperature eventualy drops down.

Can we say " I'll give him some antibiotics to drop down the temperature."?

When talking about temperature (as opposed to a falling object), the verb 'drop' is intransitive. The transitive equivalent is 'lower', so you can say "I'll give him some antibiotics to lower his temperature."

The phrasal verbs other have suggested (such as 'bring down') are also acceptable.