The health insurance exchanges are now up and running. But there are still so many big unknowns about the Affordable Care Act. To help demystify the new health care law, NBC News chief medical editor Dr. Nancy Snyderman answers your questions from Twitter and Facebook. Dont' see what you need here? Ask away using the hashtag #AskDrNancy.

Today

A. If you have insurance through your employer, you don't need to do anything -- you're already considered covered. If you want to come off your employer's insurance and shop in the marketplace, you can. But this is where doing your homework counts. Compare the plan offered by your employer to those offered in the marketplace. Keep in mind that most people who have access to employer-based coverage won't be eligible for a tax credit to help pay for a different plan.

Today

A. Your premiums will be billed directly by the insurer whose plan you choose to enroll in. The insurer will provide various payment options. Whether you pay the full amount will depend on your eligibility for a subsidy.

Q.Dennis Hackbarth (Fulton, Ill.) on Facebook: If we already have health insurance will the premium go up or will it stay the same?

A. This is a question a lot of people have been asking, but the answer isn't quite clear yet. Experts say that the major changes will be for those who buy insurance on their own. For those with employer coverage, premium costs won't change based on the law, though employers can make changes if they choose. Companies with fewer than 50 employees even have the option to drop coverage altogether.





Q. Ann Haden (Birmingham, Alabama) on Facebook: How will the tax credits work? Will I get a discount at time of purchase or must I wait to be credited at tax time next year?

A. The tax credits work two ways: You can use them right away when you sign up on the exchanges to help lower your premium costs immediately or you can get them the form of an estimated tax refund. Keep in mind that if your income changes during the year you will need to report that into the exchange and it may affect any subsidy you are getting.



Q. Cindy Baker Trevino (Martinsburg, W.Va) on Facebook: I'm just wondering if ALL doctors will be required to accept patients that are a part of this healthcare act, or will they have the option to "opt out" of seeing certain patients?

A. This is another question that we've heard a lot, but the answer is complicated. It's not clear yet whether all doctors will have to accept patients covered by plans in the exchanges. The doctors available to you will depend on the plan that you choose.

Q.Joanne Fitzgerald Ross (Grosse Pointe Park, Michigan) on Facebook: My husband is self-employed. May he obtain insurance for himself under the exchange so I can then switch to an employer covered plan just for myself?

A. Someone who is able to receive coverage through a spouse's plan can still choose to shop in the exchanges, but he or she won't be able to receive a tax credit if a plan is purchased from an exchange.

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A. An uninsured 21-year-old who doesn't sign up for health insurance may pay a penalty for being uninsured. But under the new law, young adults can stay on a parent's plan up to age 26. The other options for students are to look into plans offered by your school, or to shop in the marketplace.



A. Health care benefits kick in on Jan. 1, 2014. For women, the new law mandates cover for screenings such as mammograms, some gene testing, as well as maternity and newborn care. If your doctor prescribes birth control pills, you can now get them without paying a co-payment, co-insurance or a deductible fee.





A. The health insurance marketplaces will be open for enrollment from Oct. 1, 2013 to March 31, 2014. If you are laid off after that time, you can still apply for coverage citing a change in circumstances, otherwise known as a "qualifying life event." Marriage, divorce and having a kid also fall into this category.





A. Citizens who live abroad aren't required to have health coverage under the new health law, and they won't pay a fee for being uninsured.

Q. Is insurance mandatory?



A. In 2010, the House of Representatives and the Senate passed sweeping legislation called the Affordable Care Act, or Obamacare. The intention is to offer insurance to the more than 48 million Americans who currently have no insurance. One of the most controversial parts of the Affordable Care Act is that it’s mandatory, which means there’s a penalty if you don’t sign up for health insurance.



If you already have insurance through your employer, there’s nothing to worry about; there’s nothing to do. But if you don’t have insurance, that’s why you need to go to the exchanges, and there’s a penalty if you don’t sign up.

There are some exceptions for coverage in the Affordable Care Act. If you’re an undocumented worker, have religious issues, or you’re a Native American, you can have an exemption, which means you don’t have to have coverage at all.

Q. What are health-care exchanges?



A. One of the hallmarks of the new law are these exchanges. This is really a word for the marketplace, which means you get to go shopping. So, let’s say you have diabetes and you have to figure out what kind of health-care coverage is good for you, you go to your state's website, and depending on which state you live in, you can find various insurance plans and then tailor them to yourself.



The important date for sign up is Oct. 1, 2013. And then the benefits kick in Jan. 1, 2014.





Q. What if I have a pre-existing condition?

A. One of the strengths of the Affordable Care Act is that you can no longer be denied medical coverage because of a pre-existing condition.



So, if you have diabetes or a history of heart disease, you can get insurance like everybody else. In addition, a pre-existing condition will not affect the cost of your monthly premium and you can choose from the same plans as everyone else in your state.

In addition to being able to get health coverage, you’ll also have better access to screening, which is important for women of childbearing age.

And for older Americans who have Medicare, that doughnut hole of prescription drug coverage goes away.

These are the strengths, and some people would say the tent poles, of Obamacare.

Q. How much will coverage cost?



A. How much you make and how many people you want to have covered will determine how much you have to pay per month for coverage. Now the federal government has said it will help subsidize people in the form of tax breaks, so this is one time where you have to do your homework. Go to healthcare.gov, look at how much you make, how many people you need to cover, and that’s where you’ll get your answer as to how much it’s going to cost you every single month to get the coverage you need.

Q. What will older Americans gain or lose if already on Medicare?

A. If you’re on Medicare, you’re already covered and you don’t need to worry about signing up for insurance. And you may even see some expanded benefits for check-ups and drug coverage.

Q: Starting next year, everyone will be required to get health insurance or they will face a fine. How much is the penalty?



A: Starting in 2014, if you do not have health coverage, you will be penalized when you file your tax return the following year. For an individual, the fee is a minimum of $95, or 1 percent of adjusted income -- whichever is greater. For a family, the minimum penalty can't be more than $285 -- but it can go as high as 1 percent of adjusted family income.

Within two years, there's quite a jump. In 2016, the penalty is $695 for every adult, and the minimum penalty for a family is capped at $2,085. However, it can be as high as 2.5 percent of the family income -- whichever is greater.

Q: So, where do I sign up?

A: Go to healthcare.gov to fill out an application and check out your options for health-care coverage. There's also an 800 number already available 24 hours a day, seven days a week. It's 1-800-318-2596 and you can speak with someone who can help you through the process.

