Most people with psoriasis begin with topical treatments such as corticosteroids, coal tar, moisturizers, and vitamin A or D derivatives. But topical treatments don’t always completely eradicate psoriasis symptoms. If you’re living with moderate to severe psoriasis, you may want to consider progressing to a systemic treatment.

Systemic treatments are taken orally or through injection. They work inside the body and attack the physiological processes that cause psoriasis. Biologics such as infliximab (Remicade), adalimumab (Humira), and etanercept (Enbrel) and oral treatments such as methotrexate and apremilast (Otezla) are all examples of systemic drugs. If you’re interested in switching to a systemic treatment, here are some questions to ask your doctor to help you weighs the pros and cons.

It can take a few months for any new treatment to work. According to the National Psoriasis Foundation’s Treat 2 Target goals, any new treatment should bring psoriasis down to no more than 1 percent of your body surface area after three months. That’s about the size of your hand.

Depending on the systemic medication you take, your doctor may recommend using additional moisturizers and other topical treatments as needed. This will depend on your own personal health history and whether your doctor wants to keep you on one medication in order to assess how well it’s working.

Each type of systemic treatment comes with a unique set of risks. Biologics lower immune system activity and therefore increase the risk of infection. The same is true for most oral medications, although the specific risks depend on the kind of drug your doctor prescribes.

According to the Mayo Clinic, some systemic psoriasis medications are prescribed only for short periods of time. This is because certain systemic drugs may cause serious side effects. Cyclosporine, for example, is taken for no longer than a year, according to the National Psoriasis Foundation. If you take one of these drugs, your doctor may recommend alternating treatment with another kind of medication.

Unlike most topical medications, systemic treatments must follow a specific schedule. It’s important to review with your doctor the frequency of doses and how the doses are administered, as they can vary widely. For example, acitretin is typically taken once a day, while methotrexate is usually taken once a week.

In addition to going over the specifics of your treatment, your doctor should also alert you to any supplements or other medications that interfere with the new drug.

Systemic medications vary widely in their mechanism of action, and some are new to the market. Ask your doctor if the medication they prescribe is accessible to you. In some cases, it may be possible to try a different medication accepted by your insurer before turning to a newer treatment that isn’t covered.

If you don’t meet your treat-to-target goals, your doctor should have an alternative treatment option. This may include switching to another systemic medication and not necessarily returning to topical treatments alone. Before transitioning to a systemic medication for the first time, you can ask your doctor for a long-term path for treatment if you experience challenges in healing.

It’s essential that you know everything you can about your new medication. The National Psoriasis Foundation has a helpful overview of most system treatment options. Your doctor may also provide you with general information on living with psoriasis.

Because systemic psoriasis medications work quite differently from topical treatments, it’s important to have an open conversation with your doctor. You have many options for managing psoriasis symptoms. By gathering as much information as possible, you will be better equipped to make choices about your health in the following months.