What it is (and what it is not)
In normal skin, cells take about a month to travel from the deep layer to the surface and shed. In psoriasis that cycle accelerates to a few days. The result is a build-up of cells: the plaque — thickened, red, covered in whitish or silvery scale — typically on elbows, knees, scalp, lower back and nails.
Three things to say at the outset, because they do the most damage when ignored: it is not contagious — you can shake hands, hug and share a pool with someone who has it; it is not a fungus or an infection, so antifungals do nothing; and it is not poor hygiene. It is the immune system, and the social stigma this disease carries is frequently worse than the plaques.
What lies beneath: it is not only skin
This is the fact that changes management and that many patients do not learn for years: up to a third of people with psoriasis develop psoriatic arthritis — joint pain, stiffness and swelling, worst in the morning, in fingers, wrists, knees or spine. Detected late, the joint damage can be irreversible.
Moderate-to-severe psoriasis is also associated with increased cardiometabolic risk: hypertension, dyslipidaemia, metabolic syndrome. So correct management does not end at the cream: it includes asking about the joints and watching metabolic health.
If you have psoriasis and your joints hurt in the morning, say so. It is not “age-related” arthritis until someone rules that out.
The triggers you can actually control
Psoriasis flares in response to stimuli, and some are in your hands:
- Stress: the most reported trigger, and the most underestimated.
- Infections: a streptococcal throat infection can set off a flare (guttate psoriasis is the classic example, especially in young people).
- Skin trauma: a scratch, a burn or a scar can raise a new plaque exactly there. It is called the Koebner phenomenon, and it explains why scratching makes it worse.
- Certain drugs and, notably, abrupt withdrawal of systemic steroids, which can cause a severe rebound.
- Alcohol and tobacco: they worsen the disease and reduce treatment response.
- Sunlight, by contrast, usually helps — hence phototherapy — although sunburn does the opposite.
How it is treated
Treatment is stepped according to extent and impact on your life, and it is decided and supervised in the dermatology consultation. No drug names or doses are published here:
- Localised disease: topical therapy under prescription, plus barrier care (moisturising is not cosmetic here: it reduces scale and itch).
- Extensive or resistant disease: phototherapy — narrowband UVB or PUVA — in a cabin, on a schedule. One of the most effective and least appreciated tools. See phototherapy.
- Moderate-to-severe disease: systemic and biologic therapy, under strict specialist supervision with monitoring bloods.
- Always: rule out psoriatic arthritis and watch cardiometabolic risk.
- Never: stop a systemic steroid abruptly on your own. The rebound can be severe.
The honest expectation
With the right treatment, most patients achieve almost clear skin and long quiet periods. That is an excellent result and it is what we aim for.
But psoriasis is a chronic disease: it is not cured, and it will flare again at some point — after an infection, a stressful season, a change of treatment. A relapse does not mean the treatment failed or that you did something wrong. It means the disease is still there and it is time to regain control.
Anyone promising to cure your psoriasis definitively — with a cream, a diet or a device — is making a commercial promise, not a medical one.
Who treats it here
Diagnosis and treatment of psoriasis belong to the clinic’s dermatology consultation — the same one with which Dr. Francisco Arellano Ocampo founded the house in 1971. Dr. Arístides Arellano is a plastic surgeon, not a dermatologist: his contribution here is surgical and reconstructive, and the disease itself is managed in the consultation. Book at dermatology consultation.
The institutional advantage is concrete: clinical dermatology is the root of this house — it is what it was founded on in 1971 — and the phototherapy cabin is in the same building as the consultation.
Dr. Arístides Arellano is a plastic surgeon holding a specialty licence: he practises under a Mexican medical licence (D.G.P. 1125959) and a specialty licence in Plastic & Reconstructive Surgery (0002008), both issued by the Directorate General of Professions (DGP), which reissued his certificate of professional standing in 2025. His career began before Mexico’s present-day specialty-board system existed: he belongs to the founding generation of plastic surgery in Puebla, the second generation of a surgical tradition started in 1971 by Dr. Francisco Arellano Ocampo. Trust is verified, not promised: both licences are public and anyone can look them up in the DGP’s National Registry of Professionals.
Risks and expectations
Every medical treatment —topicals, peels and energy-based devices included— carries risk and requires a prior assessment. In darker skin (Fitzpatrick IV–VI, the most common phototypes in Mexico) a poorly indicated procedure can darken the patch instead of lightening it. Results may vary according to each patient, their phototype and their individual triggers.
Trust is verified, not promised. All 210 scanned documents —degree, licences, diplomas, publications and certificates, from 1977 to 2025— are open in Dr. Arístides Arellano’s credential archive, alongside an explanation of the difference between a specialty licence and a board certification.
Control and follow-up plan
- DiagnosisDermatology consultation. Extent, nails, scalp — and JOINTS — are assessed.
- Localised diseaseTopical therapy under prescription + barrier care.
- Extensive diseaseNB-UVB or PUVA phototherapy, on a session schedule.
- Moderate-to-severeSystemic or biologic therapy, with supervision and monitoring bloods.
- AlwaysRule out psoriatic arthritis. Watch cardiometabolic risk.
- RelapseExpected, not a failure. Control is regained.
Frequently asked questions
Can psoriasis be cured?
No. It is a chronic immune-mediated disease: it is controlled very well, with long periods of almost-clear skin, but it flares again at some point. A relapse does not mean the treatment failed; it means the disease is still there. Anyone promising a definitive cure — with a cream, a diet or a device — is making a commercial promise, not a medical one.
Is psoriasis contagious?
Not at all. It is not an infection and not a fungus: it is the immune system accelerating skin renewal. You can shake hands, hug, share a towel and swim in the same pool as someone with psoriasis with no risk whatsoever. The social stigma of this disease usually does more harm than the plaques.
Is it a fungus? Will an antifungal cream help?
It is not a fungus and antifungals do nothing. It is one of the commonest confusions, especially when nails or scalp are involved, and it leads to months of useless treatment. Diagnosis is made in the dermatology consultation, and sometimes requires a biopsy to distinguish it from other diseases.
Why do you ask about my joints?
Because up to a third of people with psoriasis develop psoriatic arthritis, and if it is found late the joint damage can be irreversible. If you have joint pain or stiffness, especially in the morning, in fingers, wrists, knees or spine, say so: it is not age-related arthritis until someone rules that out.
What triggers flares?
Stress is the most reported. Also infections — a streptococcal throat infection can set off a flare — skin trauma (scratching raises new plaques exactly there), alcohol, tobacco, certain drugs and, very importantly, abrupt withdrawal of systemic steroids, which can cause a severe rebound. Sunlight, by contrast, usually helps.
Does phototherapy work?
Yes, and it is one of the most effective and least appreciated tools in extensive disease. It is delivered in a cabin, with narrowband UVB or PUVA, on a session schedule. It is prescribed and supervised in the dermatology consultation, and the cabin is in the same building.
Every case is different. Discuss yours in a personal consultation.
Book a consultation on WhatsAppEvery figure published on this site is approximate and is not a quote. Any procedure or treatment first requires a private assessment consultation with Dr. Arístides Arellano —$800 MXN, charged separately— and it is at that consultation that the definitive cost of your case is determined.
Educational content; it does not replace a medical consultation. Results may vary from person to person.