Psoriasis is a skin disease that causes raised skin lesions, such as scaly patches. On brown, black, and white fur, the spots may appear pink or red, and the scales white or silver. On brown and black fur, the spots may also appear purple or dark brown, and the scales may appear gray.
Although it is true that psoriasis can appear on all skin types, it is more common on white skin. Similarly, although it is more common to affect the elbows, scalp and knees, it can appear in other parts of the body.
The reason for this disease is not known, although it is known how it occurs and what are some of the factors that can trigger the disease. Today we are not going to delve much into how, into the pathogenesis, since it is complex and requires its own article. In any case, it is worth mentioning that we know that psoriasis is a chronic inflammatory disease, that is, that inflammation is an essential process in its production. We recently published an article on inflammation, in case you want to dig deeper. One of the phenomena facilitated by inflammation is the communication between different cells of our body. This is important because psoriasis occurs when the immune system attacks healthy skin cells.
Since there is not much we can do to prevent an already established autoimmune disease, it is perhaps more appropriate to discuss some of the triggers for this condition, such as smoking, obesity, strep throat, and even the cold. Curiously, humidity, heat and sun are beneficial. Finally, there are two very important factors that we can probably influence: stress and drugs.
Indeed, some medications can also be the cause of this disease. Let’s see some of them.
antimalarial drugs
Antimalarial drugs are used to prevent malaria and treat rheumatoid arthritis and lupus. Chloroquine and hydroxychloroquine are the most widely prescribed. Perhaps they are familiar to you because they were tried to be used at the dawn of the COVID-19 pandemic, finally ruling out their use as ineffective against SARS-CoV-2. However, psoriasis can be a side effect of both drugs.
Although these medications are linked to psoriasis, they do so significantly more in worsening established psoriasis than in causing the problem itself.
Antimalarials can cause psoriasis by inhibiting the production of the enzyme transglutaminase in the skin. This affects cell production and leads to a type of psoriasis, pustular psoriasis.
For the skin lesions of psoriasis to develop, it usually takes between 2 and 12 weeks after the start of antimalarial therapy. Psoriasis lesions may disappear within a month if the person stops taking this medication.
Beta blockers
Beta-blockers are drugs that help us treat various diseases of the cardiovascular system. For example, they help us reduce the heart rate when it is triggered in some types of arrhythmias. Well, unfortunately, one of the possible side effects of taking beta-blockers, primarily propranolol, is psoriasis. Specifically, it can cause the most common type of psoriasis, plaque psoriasis. Fortunately, although this side effect has been described, it is rare. And even more infrequent, although possible, it would be that other types of psoriasis, known as erythrodermic psoriasis and palmoplantar pustular psoriasis, would precipitate.
Lithium
This is one of the important drugs to take into account in relation to this disease. Lithium is a mood-stabilizing drug that doctors prescribe to treat bipolar disorder. Lithium can cause different types of psoriasis in people who do not have a family history of the disease. Unfortunately, they can also cause psoriatic arthritis, a form of arthritis in patients already affected by psoriasis.
Anecdotally, it is worth mentioning that a few isolated studies have found that inositol supplements may be effective in treating worsening psoriasis in people receiving lithium therapy. Inositol is found in the brain and tissues. Its structure is that of a sugar. Its function is to help balance some chemicals in the body.
Just like that
Imiquimod is an immunomodulator. It is prescribed as a local therapy for conditions such as warts and some types of skin cancer.
Therapy with this drug may worsen pre-existing psoriasis in adults. Interestingly, this drug can also cause psoriasis in children. The type of psoriasis, when it occurs, is usually the usual one, in plaques.
On the other hand, there is the possibility of successfully treating imiquimod-induced psoriasis with conventional treatment of the disease.
Interferons
Interferons are used to treat diseases such as hepatitis C, multiple sclerosis, and some cancers.
One of the medications for the hepatitis C virus, interferon-alpha, can cause psoriasis and worsen the condition of pre-existing psoriasis.
On the other hand, in these cases the symptoms usually improve markedly after stopping the treatment, although sometimes it is also a good idea to apply the usual antipsoriatic treatment.
The drug for multiple sclerosis is Interferon-beta, and it is a drug that can also cause psoriasis and worsen pre-existing symptoms.
Nonsteroidal anti-inflammatory drugs (NSAIDs)
This is, perhaps, the most important group of drugs of those mentioned. This is because these are the most widely used drugs. This pharmacological group is used to relieve pain and inflammation. Some of the most used are aspirin and ibuprofen, for example.
People with psoriasis can often use NSAIDs. However, we must be cautious and aware, since in some cases a worsening of psoriasis symptoms has been observed due to the use of these drugs.
If a person has psoriasis, depending on their particularities, their doctor may assess pain control with other types of drugs. In any case, there is no recommendation applicable to all patients, since there are different variables to take into account, such as the duration of treatment.
Terbinafine
Terbinafine is prescribed to treat fungal infections. Terbinafine may cause or worsen the symptoms of plaque psoriasis, pustular psoriasis, and inverse psoriasis.
TNF inhibitors
Tumor necrosis factor (TNF) inhibitors are used to treat inflammatory conditions such as inflammatory bowel disease, rheumatoid arthritis, psoriasis, and psoriatic arthritis.
These drugs act by reducing the production of tumor necrosis factors and lead to a reduction in inflammatory processes.
However, TNF inhibitors can also cause psoriasis or worsen existing symptoms.
If psoriasis is mild, doctors may decide to continue treating the person’s underlying disease with TNF inhibitors and treat psoriasis with topical steroids, UV therapy, or drugs such as methotrexate or cyclosporine.
However, if a severe form of psoriasis occurs, the doctor may decide to substitute the medication.
It’s true that there are more drugs you may hear mentioned as psoriasis triggers, such as ACE inhibitors (antihypertensive drugs), biologics (monoclonals), benzodiazepines (such as diazepam), and some antibiotics. It is true that there are some communications that describe these cases. However, they are scarce and currently there are not enough studies that clearly demonstrate this association.
What NOT to do?
There is a possibility, after reading this article, that if a person has a medication mentioned in their treatment, they decide to stop taking the medication. It must be taken into account that medication changes should be made in consultation with the doctor . Many of the drugs mentioned are not drugs for general ailments, but for specific pathologies, which act in a certain and particular way. It is reasonable to bear in mind that its administration is not safe, but there are cases in which the benefits can clearly outweigh the potential harm . Therefore, relevant health decisions should be made in consultation with a trained professional. This is also because the suppression of treatment with powerful systemic or topical corticosteroids can be another well-documented cause that triggers an outbreak.
References:
Balak, D. M., & Hajdarbegovic, E. (2017). Drug-induced psoriasis: clinical perspectives. Psoriasis (Auckland, N.Z.), 7, 87–94. https://doi.org/10.2147/PTT.S126727
How long will I have to treat my psoriasis? (s.f.). American Academy of Dermatology Association. https://www.aad.org/public/diseases/psoriasis/treatment/medications/how-long
Kim, G. K., & Del Rosso, J. Q. (2010). Drug-provoked psoriasis: is it drug induced or drug aggravated?: understanding pathophysiology and clinical relevance. The Journal of clinical and aesthetic dermatology, 3(1), 32–38. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2921739/
Li, S. J., Perez-Chada, L. M., & Merola, J. F. (2019). TNF Inhibitor-Induced Psoriasis: Proposed Algorithm for Treatment and Management. Journal of psoriasis and psoriatic arthritis, 4(2), 70–80. https://doi.org/10.1177/2475530318810851
Psoriasis (2022). NHS. https://www.nhs.uk/conditions/psoriasis/
Zhang L. J. (2019). Type1 Interferons Potential Initiating Factors Linking Skin Wounds With Psoriasis Pathogenesis. Frontiers in immunology, 10, 1440. https://doi.org/10.3389/fimmu.2019.01440
