The best way to determine if ACE inhibitors are linked to worsening psoriasis in a given patient is to ask if the psoriasis got more unruly with dose increases, which would suggest that the ACE inhibitor had a role in the psoriatic process, Dr. Heald said. If you suspect ACE inhibitor involvement, “talk with the patient's internist about switching medications,” he said, noting one caveat: “Often the first words out of the internist's mouth are 'let's put them on one of these new angiotensin receptor antagonists,' which may not be a good idea because there has been at least one report linking those to the development of pustular psoriasis.”
Because there are alternative antihypertensive medications, it's not necessary to treat the psoriasis through the ACE inhibitor therapy. “It's best to just go off that class of drugs completely,” said Dr. Heald. “If after 6 months off [the ACE inhibitor] there's no change in scenario, you can feel comfortable restarting the drug knowing you considered the possibility.”
β-Blocker Psoriasis
It's fairly common knowledge that β-blockers have some connection with psoriasis, but there is not a lot of literature to provide insight into the association, Dr. Heald said. “The literature has three scenarios that have occurred with β-blockers and psoriasis—two of which would be hard to miss. One is a psoriasiform drug eruption and the other is conversion to pustular psoriasis within 1 month of starting the drug,” he said. The third, less obvious scenario is an insidious worsening of psoriasis over time in the presence of a β-blocker on the medication list.
“There's no blood test that you can do and there are no good guidelines for pursuing [the association],” said Dr. Heald, who recommended running through a list of questions when considering the possibility of β-blocker psoriasis. “If the problem has arisen within 4 months of initiating the drug, you've got to pursue it. But before talking to the patient about an expensive therapy such as [etanercept], you have to ask yourself if you are really just treating what could be taken care of by eliminating just one drug off the medication list,” he said. If so, “that should lead you to question whether the risk of the medication for the psoriasis is more or less than the risk of switching away from the β-blocker.”
Because there are usually good alternatives for β-blockers in most patients, “I think a 12-week break makes sense,” Dr. Heald said. “Most studies show that if resolution is going to happen, it will be within 3 months of stopping the drug. If you recommend this to the patient and his or her [primary care physician] or cardiologist, you insert yourself as being a caring physician, because they know you're looking for a way to treat this without adding on another medication.”
Antimalarial Psoriasis
“I recently saw a patient who started on an antimalarial medication to treat symmetric polyarthritis with psoriasis. Within 2 weeks of starting the drug, he began to develop what I call a 'fill in the gap' type of psoriasis, in which erythema develops in between preexisting plaques,” Dr. Heald said. “We've seen a bunch of these cases because for a while at our Veterans [Affairs] hospital a patient had to fail an antimalarial before getting approval for treatment with a biologic for psoriatic arthritis.” To manage this condition, “we stop the drug immediately and switch over to something that can treat both [psoriasis and psoriatic arthritis] and possibly a prednisone taper,” Dr. Heald said. “I don't think psoriasis patients should ever be put on antimalarials. Hydroxychloroquine inhibits epidermal transglutaminase activity, which leads to irregular keratinization and dermoepidermal detachment and cleft formation. In psoriatics, this leads to an erythrodermic form of the disease.”
Efalizumab-Interruption Psoriasis
Most dermatologists have legions of happy psoriasis patients thanks to the efficacy of biologics for continuous control of their conditions, “but there is one little side to this that has not been published enough: the possibility of psoriasis exacerbation when treatment is interrupted,” said Dr. Heald, who has had patients weeks and even months into successful therapy whose psoriasis returns with a vengeance following two or three missed doses. “One of my patients went on a trip and forgot his medication for 3 days. He experienced an unbelievably quick, abrupt aggravation with lots of very pruritic new lesions and oozing lesions.” It's unclear what's behind this, he said, but it's possible that with an interruption in therapy “all those cells go barreling back into the skin and create this abrupt syndrome.”