Employee medicare went up 62.07% in September. why?

I can help you provide insights into your medicare rate concerns, pam109.

The Medicare tax is subject to Additional Medicare Tax Withholding if paid more than the $200,000 withholding threshold. 

The tax has a rate of 1.45% w/ the Additional Medicare tax of 0.9%. That's why the overall tax rate is 2.35%. For additional information, check the following article: Social Security and Medicare Withholding Rates.

Do you need help running payroll reports? This article provides several reports you can read to take a closer look at your business and employees for a complete guide: Run payroll reports in QuickBooks Online. 

I've got your back if you need more help with payroll tax rates or any related concerns in QBO.