Prescription Psoriasis Drugs - topical and internal.
Psoriasis is an overactive inflammatory immune response. All of the prescription drugs are immunosuppressive and target different things in the inflammatory signaling pathways to down-regulate the inflammatory response. None of them address the original sources of inflammation. Psoriasis takes small amounts dietary/immune inflammation and multiplies the inflammation down an adaptive immune system pathway. This multiplication can't be reversed, and can be hard to control, so drugs can be useful.
I have tried most of the topicals, and have not tried most of the internal drugs.
Topical skin ointments
Topicals are generally safer than the internal drugs, in terms of side effects and localizing the dose. Topicals can be washed off and immediately discontinued if side effects appear. They can be messy, frustrating, and socially annoying to administer: applying ointments all over your body multiple times a day, having shiny ointment on your patches, getting them on clothes and furniture, and possibly in unsafe areas like the eyes, mouth and other people.
Calcitriol ("Rocaltrol", "Calcijex", "Decostriol", "Biowo", "Vectical", "Rolsical") - vitamin D3 analog that does vitamin D3 and calcium activity. Rare side effect is hypercalcaemia, excess calcium that makes you sick with headache, vomiting, etc., especially if over-supplementing vitamin D. It can cause skin irritation. I find it calms skin better than aloe or shea, and works well in combination with them. It can temporarily make my skin extra hot and red with exercise or stress. It's pretty greasy and shiny, I don't like how it looks during the day. After a few hours, when it's all absorbed, is when the skin looks best. It does actually help the skin heal long term if you can get down the inflammation causing it.
Calcipotriol ("Dovonex", "Daivonex", "Psorcutan") - is a calcitriol derivative. Very much similar to calcitriol in every way. May also cause photosensitivity to sun and UV.
Tacrolimus (FK-506, fujimycin, "Prograf", "Advagraf", "Protopic") - 23-membered macrolide lactone that targets IL-2. side effects include skin irritation, acne, flu symptoms. For me, this stuff does not do anything more than aloe or shea, it's like a semi-dangerous moisturizer.
Clobetasol propionate ("Clobex", "Clob-x", "Clovate", "Cormax", "Pentasol", "Cosvate", "Temovate", "Dermovate", "Olux", "Tenovate", "Dermatovate", "Butavate", "Movate", "Novate", "Powercort") - glucocorticoid corticosteroid. It's a potent topical steroid. Side effects are skin irritation, rash, photosensitivity, tiredness, dizziness, thirst, vision or breathing problems. I will only use this stuff short term on special occasions. It takes the redness out noticeably where the patch is calm and a ring of skin around it is all white. It thins and damages your skin long term, and you build up a tolerance where it stops working. It doesn't help heal the psoriasis it just hides it until you stop using it, and then it's worse than it was to begin with. The special cases where this stuff is very useful are: poison ivy, too much sun, or the day before a special event.
To use to clobetasol to help maximize sun healing effect, use a sun oil (RedGreenTea™) before sun, get as much sun as possible without any sun burn, apply aloe butter (HotChocAloe™) full body after sun, then spot treat psoriasis with clobetasol. This will maximize D3 and healing immunosuppression from the sun, while minimizing damage and inflammation.
I usually keep Calcitriol and Clobetasol on hand, but I find them less important than normal moisturizing oils.
Internal pills and injections
The internal drugs for psoriasis have a laundry list of major side effects, and are a little scary. None of them stays as effective long term. Most of them are taken weekly or monthly, which is convenient, but you can't discontinue the effects immediately in the event of side effects, disease or illness. And they are expensive.
Here are the internal drugs by date. The earliest MTX was originally a chemotherapy drug and is and anti folate. The rest are biopharmaceutical (biologics), which block specific inflammatory immune signaling. Biologics are not made via chemistry like normal drugs. Vaccines are examples of early biologics, but modern biologics for psoriasis are made by inserting genetically modified genes into huge quantities of specific living cells to produce specialized proteins. This is why they are so expensive. There are no generics for any of these biologics yet.
I just started taking MTX for the first time. It have not seen any effects or side effects yet. I have never taken any of the biologics.
Methotrexate (MTX, amethopterin) 1950s - antimetabolite antifolate. Side effects include severe liver damage, hair loss, nausea, headaches, pigmentation, drowsiness. To minimize side effects: take folate (folic acid, Vitamin B9), and avoid alcohol, fructose, and other liver toxins. This was found to treat psoriasis on accident. It was originally a high dose chemotherapy drug for cancer. In low doses for psoriasis it's relatively safe.
Etanercept ("Enbrel") by UT/Immunnex/Amgen/Pfizer 1993 - biologic, targets TNF. TNF-alpha is a top-level signaling protein in the innate immune system. In addition to clearing up psoriasis, this biologic shuts down major branches of the immune system opening the door to potentially deadly infections and diseases, especially TB and cancers. This is the reason for the extremely broad and serious list of side effects.
Adalimumab ("Humira") by AbbVie 1993 - biologic, targets TNF. Same description as Etanercept.
Ustekinumab (CNTO 1275, "Stelara") by Centocor/Janssen 2003 - biologic, targets IL-12 & IL-23. IL-12 & IL-23 are inflammatory proteins in the middle of the adaptive signaling pathway. Deadly infections and diseases, upper respiratory infections, injection site reactions, tiredness, confusion, seizures, brain swelling, and temporary vision loss.
Secukinumab ("Cosentyx") by Novartis 2013 - biologic, targets IL-17. IL-17 is probably the key inflammatory protein near the end of the adaptive pathway for plaque psoriasis. So far: common cold, upper respiratory infections, injection site reactions, tiredness.
Ixekizumab (LY2439821, no brand name yet) by Eli Lilly 2013 - biologic, targets IL-17. IL-17 is probably the key inflammatory protein near the end of the adaptive pathway for plaque psoriasis. So far: common cold, upper respiratory infections, injection site reactions, tiredness.
Brodalumab (AMG 827, no brand name yet) by Amgen/AstraZeneca 2013 - biologic, targets Th17. Th17 is the T-helper cell that makes IL-17 which is probably the key inflammatory protein near the end of the adaptive pathway for plaque psoriasis. So far: common cold, upper respiratory infections, injection site reactions, tiredness.