I heard the amount changed again.
For the 2017 and 2018 tax years, all taxpayers can write off health care expenses that exceed 7.5% of their income. In 2019, the threshold goes back to 10% of income.
Does this include monthly premiums I pay for health insurance?
Yes, if you paid for health insurance premiums out of pocket, then these would be deductible if you itemize. For a full list of deductible medical expenses, see IRS link below.
Medical and Dental Expenses Pub 502