Today.

I am ill. I have a high temperature and cough . The doctor wroute me many prescriptions. a mountain of medications.

Today

Technically, medications aren't written. "Prescriptions" would probably be more appropriate.

Today.

I am il. I have a high temperature and cough . The doctor wroute a mountain of medications.

Today.

I am ill.  I have a high temperature (you can also say "I have a fever") and cough.  The doctor wrote me many (you could also replace many with: "a bunch of" or "several") prescriptions.

Note: While I understood "a mountain of prescriptions", this term is usually used when there is a lot of physical things - for example "A mountain of paperwork", "a mountain of old shoes", "a mountain of newspapers".  In the US, prescriptions usually come on a small square piece of paper.  It would be better to say "several" or "many".  Even if the doctor gave you 10 prescriptions, it would still sound odd in English to hear "a mountain of prescriptions."  

You could say - "The doctor gave me a mountain of pills" (pills are a physical object")

Today.

I am ill, I have a high temperature and cough. The doctor wroute  wrote a mountain of medications prescriptions(the names a quantities of medicines you need).