Psoriasis Injections

Psoriasis injections are commonly used in people with moderate to severe psoriasis who do not respond to topical or oral treatments. Methotrexate, an immune suppressant drug, and biologic drugs such as Enbrel (etanercept), Humira (adalimumab), and Stelara (ustekinumab) are examples of injectable psoriasis medications.

In addition to these, injected corticosteroids (steroids) may be used on occasion to bring a psoriasis flare-up under control.

Each of these injectable drugs works differently but ultimately dampens the overactive immune response that triggers psoriasis and psoriatic arthritis symptoms.

This article describes the different injectable drugs used to treat psoriasis, including the recommended dosage and prescribing information. It also provides step-by-step instructions on how to give yourself a psoriasis injection.

Injectable Methotrexate for Psoriasis

Methotrexate is a drug used to treat certain cancers and autoimmune diseases like rheumatoid arthritis and psoriasis. It is both an immunosuppressant (meaning that it suppresses the immune system) and an antiproliferative agent (meaning it slows the growth of cells).

These actions are useful for autoimmune diseases, as these involve the body's own immune system attacking normal cells, causing inflammation. With psoriasis, the inflammation causes skin cells to proliferate and accumulate faster than they can be shed, leading to itchy, scaly patches called plaques.

Because methotrexate hampers the underlying cause of autoimmune diseases, it is classified as a disease-modifying antirheumatic drug (DMARD).

Recommended Dosages

Methotrexate may be given at a single consistent dose. But, due to the risk of anemia and other side effects, some healthcare providers prefer to start at a lower loading dose to get your body accustomed to the drug before increasing the optimal therapeutic dose.

The dosage of the drug is described in milligrams (mg).

A methotrexate dose can be adjusted up or down as needed to clear skin plaques with minimal side effects. It takes about a month before you will see and feel the effects of treatment.

Administration

Methotrexate is usually given by mouth but may be given by weekly injection. The injection is most often given subcutaneously (under the skin) and less commonly by intravenous infusion (into a vein).

Another benefit of subcutaneous injections is that you can give yourself shots at home; intravenous (IV) infusions need to be administered in a medical setting.

Even so, people who are unwilling or unable to give themselves shots may be better suited for intravenous methotrexate infusions.

Injectable Biologic Drugs for Psoriasis

Biologics are medicines derived from human or animal proteins, rather than those created in the lab. These drugs suppress facets of the immune response, rather than the immune system as a whole.

Although biologic drugs do cause side effects, they tend to be less severe than those of other options—which is why some experts are calling for them to be used earlier on in treatment.

Biologics are traditionally used for prescribed to people with moderate to severe plaque psoriasis or psoriatic arthritis who have not responded to other treatments or who have experienced intolerable side effects from them.

These drugs can be used on their own or in combination with methotrexate or other drugs commonly used to treat autoimmune diseases.

Among the biologics most commonly used to treat psoriasis or psoriatic arthritis are:

• Cimzia (certolizumab pegol)
• Cosentyx (secukinumab)
• Enbrel (etanercept)
• Humira (adalimumab)
• Ilumya (tildrakizumab)
• Orencia (abatacept)
• Siliq (brodalumab)
• Simponi (golimumab)
• Skyrizi (risankizumab)
• Stelara (ustekinumab)
• Taltz (ixekizumab)
• Tremfya (guselkumab)

Depending on the drug used, you may need an injection every one to 12 weeks. If there is no improvement in your symptoms after 12 to 16 weeks, the treatment is generally stopped.

Recommended Dosages

Each biologic has different preparation and dosing instructions. Your rheumatologist will walk you through what to do, but you should also read the package instructions to avoid errors.

Most biologics require a loading dose followed by the recommended therapeutic dose.

Administration

All of the biologics approved for the treatment of psoriasis or psoriatic arthritis are delivered by subcutaneous injection. These are given in areas where the skin can be pinched, such as the abdomen or thigh.

To prevent scarring, change the location of the subcutaneous injection site with every shot.

Injectable Corticosteroids

Corticosteroids (steroids) are less commonly used to treat psoriasis as their prolonged use can lead to serious side effects like glaucoma and osteoporosis.

Even so, injected steroids have their place in the treatment of severe psoriasis flare-ups when topical and oral medications fail to provide relief.

The main benefits of steroid injections are that they are fast-acting and the skin clearance can sometimes last for weeks or months. Even so, they are not considered the ideal choice for the ongoing treatment of psoriasis and are generally intended for short-term use.

The steroids most commonly used for the treatment of psoriasis and psoriatic arthritis include:

• Prednisone
• Methylprednisone
• Dexamethasone
• Fludrocortisone
• Hydrocortisone

Recommended Dosages

The recommended dosage of injected steroids varies by the drug used. In their current guidelines, the American Academy of Dermatology (AAD) and the National Psoriasis Foundation (NPF) do not offer recommendations for the appropriate use of injected steroids for people with psoriasis.

The choice and dose of steroid should be directed by a qualified dermatologist or rheumatologist.

As a general rule, the lowest possible dose is given to resolve the symptoms.

If used for a longer period of time, the steroid dose will need to be tapered down gradually to avoid withdrawal and a rebound of psoriasis symptoms.

Administration

Steroid injections are typically delivered by intramuscular injection (into a large muscle like the buttocks).

For severe psoriatic arthritis flare-ups, an intra-articular injection (into a joint space) may be given to reduce joint inflammation.

Steroid shots are not self-administered but are rather given by a healthcare provider.

How to Give Yourself a Psoriasis Injection

Methotrexate and some biologic agents are available as a single-use, prefilled syringe or a pen-like, disposable auto-injector.

The injection procedure is essentially the same for each. The only difference is that a syringe has a plunger that you depress after the needle is inserted. With an auto-injector, the unit is placed against the skin and the needle automatically lowers after you press a button.

Injectable psoriasis drugs need to be kept at temperatures between 36 and 46 degrees F. Leave your medication in the refrigerator until you are ready to use it, then follow these steps.

To self-inject yourself with a prefilled syringe:

1. Bring the drug to room temperature. Remove the syringe from the refrigerator 30 minutes beforehand. You can also warm it in your hand (but not in the oven or microwave).
2. Get your injection equipment ready. This includes an alcohol pad, some sterile gauze, an adhesive bandage, and a child-proof trash container.
3. Wash your hands. The injection must be aseptic, so use plenty of soap and warm water.
4. Cleanse the skin with alcohol. Remove the alcohol pad from the packet and rub it over the injection site in a circular motion. Allow the area to air dry.
5. Uncap the needle. Hold the syringe in one hand as would you would a pen and twist off the cap with your free hand.
6. Pinch the skin at the injection site. Whether you choose your thigh or abdomen, pinch two inches of skin between your thumb and forefinger so that there is an ample target for the injection.
7. Insert the needle. With a single quick thrust, insert the needle completely into the fold of skin at a 90-degree angle. If you do this quickly, you will feel little to no discomfort. (If you are overweight or obese, a 45-degree angle may be better. Speak with your healthcare provider.)
8. Pull back slightly on the syringe. If blood is drawn into the syringe, do not proceed. You have accidentally hit a blood vessel and need to try again on another spot.
9. Depress the plunger. If there is no blood in the syringe, slowly depress the plunger all the way down.
10. Remove the needle. Hold the alcohol pad over the injection site. Do not rub.
11. Bandage the skin, if needed.
12. Dispose of the syringe and used injection equipment. Carefully cover the needle with the cap. For extra safety, place the syringe back into its original box or in a puncture-resistant container (like a milk carton) before disposing of it in a covered garbage can.

To inject yourself with a disposable auto-injector:

1. Follow steps 1 through 4 above.
2. Twist off the auto-injector cap. There will usually be an arrow to show you which direction to twist.
3. Place the base of the auto-injector against your skin. The flattened base should be situated firmly and flatly against the injection site.
4. Turn the lock ring to the unlock position. This may be clockwise or counterclockwise; check the arrows.
5. Press the injection button. You should hear a loud click. This means the injection has begun.
6. Listen for the second click. This means the injection is complete.
7. Follow steps 10 through 12 above.