| Type | What it looks like | Care needed |
|---|---|---|
| Plaque | Raised, red patches with silvery-white scale, usually on the scalp, elbows, knees, and lower back | Routine dermatology care |
| Guttate | Small, salmon-pink or red dots, usually on the torso, arms, and legs; sometimes follows an infection | Routine dermatology care |
| Inverse | Smooth, raw-looking red patches in skin folds, with little of the usual scale | Routine dermatology care |
| Pustular | Pus-filled bumps on red, swollen skin, most often on the hands and feet | Routine dermatology care |
| Generalized pustular | Pus-filled bumps spread across large areas of skin, often with fever | Medical emergency - same-day care |
| Erythrodermic | Red, scaly skin covers most of the body | Medical emergency - immediate care |
| Scalp | Plaque psoriasis on the scalp | Routine dermatology care |
| Nail | Pitted, ridged, thickened, or discolored nails, sometimes lifting from the skin | Routine dermatology care |
What is plaque psoriasis, and how common is it?
The most common type: the American Academy of Dermatology says about 80% to 90% of people with psoriasis develop it. Thick, raised patches covered in a dry, silvery-white scale, usually on the scalp, elbows, knees, or lower back, though a patch can develop anywhere. Smaller patches can join into larger ones. Evidence
What is known
- Reasonably supported
The AAD names scale, thickness, and size variation as the defining look, and states that scratching can cause a patch to thicken rather than settle.
What is uncertain
- Depends on you
A population prevalence figure says nothing about how much skin one particular reader has, and appearance alone does not confirm psoriasis over another skin condition.
Worth asking a clinician
Does what you are seeing match plaque psoriasis, or does something look different from that?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What besides not scratching would help with the itch?
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What is guttate psoriasis?
Small, scaly, salmon-to-pink spots that appear suddenly, usually on the torso, legs, and arms, and sometimes the face, scalp, or ears. It is more common in children and young adults. The AAD documents some cases developing after an infection such as strep throat, and it is often temporary, clearing on its own within weeks or months. Evidence Evidence
What is known
- Reasonably supported
The AAD names strep throat as a documented trigger for guttate psoriasis developing in someone who already has plaque psoriasis. It separately describes guttate spots as often clearing without treatment.
What is uncertain
- Depends on you
"Often" clearing is not a guarantee for one reader, and the source gives no figure for how often it clears versus persists.
Worth asking a clinician
Is a recent infection likely connected to this?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Should I expect this to clear on its own, or does it look like it needs treatment?
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What is inverse psoriasis?
Smooth, raw-looking red patches with little of the silvery scale seen in plaque psoriasis. It appears where skin touches skin - the armpits, genitals, and the crease of the buttocks. The AAD describes it as often sore or painful rather than itchy. Evidence
What is known
- Reasonably supported
The AAD describes this pattern - smooth, raw, low-scale patches specifically in skin folds - as the defining look distinguishing inverse from the other types.
What is uncertain
- Depends on you
Location and look are not a self-diagnosis; friction and sweat can worsen it, and a clinician needs to examine it directly.
Worth asking a clinician
Does the location and look here match inverse psoriasis to you?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What would help with the soreness day to day?
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What is pustular psoriasis?
Pus-filled bumps on red, swollen skin, most often on the hands and feet. The AAD states the bumps are not infected - the pus is white blood cells, not bacteria - but that the pain can make typing or walking unbearably difficult. Evidence
What is known
- Reasonably supported
Brown dots and scale appear as the bumps dry. This localized form is separate from the life-threatening generalized form below.
What is uncertain
- Depends on you
The source does not name what sets off a localized pustular flare, and it does not say whether or how often it spreads beyond the hands and feet.
Worth asking a clinician
Is this contained to my hands and feet, or could it spread?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What would help with the pain when I need to use my hands or feet?
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What is generalized pustular psoriasis, and why is it an emergency?
A rare, life-threatening type where pus-filled bumps spread across much of the skin, often with fever and feeling extremely unwell. The AAD says medical care is often necessary to save the person's life, and the NICE guideline calls for same-day specialist assessment. Evidence Evidence
What is known
- Reasonably supported
The AAD describes a flare as a sequence: dry, tender, red skin developing pus-filled bumps that can join into pools of pus. The person also feels very sick, sometimes with fever, headache, and muscle weakness.
What is uncertain
- Depends on you
This names a documented emergency pattern; it does not grade a reader's own symptoms or say how fast it will move for a given person.
Worth asking a clinician
If I ever see this pattern, who do I call - your office, urgent care, or an emergency room?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What would tell me this has started, rather than a bad flare of what I already have?
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What is erythrodermic psoriasis, and why is it an emergency?
A rare, life-threatening type where red, scaly skin covers most of the body and skin can look burnt. It requires immediate medical care. The AAD lists chills, fever, a rapid pulse, severe itch, and looking extremely ill as signs, and the NICE guideline calls for same-day specialist assessment. Evidence Evidence
What is known
- Reasonably supported
The AAD states most people who develop erythrodermic psoriasis already have another type of psoriasis, and often notice it worsening or not improving with treatment beforehand. Skin covering that much of the body cannot regulate temperature normally, so hypothermia can set in quickly.
What is uncertain
- Depends on you
This names a documented emergency pattern from group observation; it does not predict who will develop it or exactly how it will present for one person.
Worth asking a clinician
What would tell me this has become an emergency rather than a bad flare?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Who do I call - your office, urgent care, or an emergency room - if this happens after hours?
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What is scalp psoriasis?
Plaque psoriasis showing up on the scalp - one of the common sites the AAD names for the plaque type. Hair loss can follow, but the AAD's own hair-loss guidance says hair tends to regrow once the scalp psoriasis clears. Evidence Evidence
What is known
- Reasonably supported
That guidance states forcefully removing scale often loosens hair along with it. That is why gentle handling matters more than how thoroughly the scale comes off in one sitting.
What is uncertain
- Depends on you
"Tends to regrow" is not a guarantee or a timeline for one reader, and persistent hair loss can have other causes worth raising separately.
Worth asking a clinician
What is the gentlest way to handle scale on my scalp without pulling hair out with it?
Saving keeps this on your device and needs JavaScript, which is off in this browser.If hair loss continues after treatment, what else could be going on?
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What is nail psoriasis?
Pitted, discolored, thickened, or crumbling nails, sometimes lifting away from the skin underneath. The AAD says about half of the people who have plaque psoriasis see some sign of it on their fingernails at some point. Evidence
What is known
- Reasonably supported
Signs include tiny dents called nail pits, white, yellow, or brown discoloration, and buildup of skin cells beneath the nail that lifts it up.
What is uncertain
- Depends on you
That figure describes people who already have plaque psoriasis, not everyone with psoriasis, and it does not say when or whether it will show up for one reader.
Worth asking a clinician
Is what I am seeing on my nails likely connected to my psoriasis?
Saving keeps this on your device and needs JavaScript, which is off in this browser.What would treatment for my nails involve, separately from my skin?
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Can you have more than one type, or have it change?
Yes to both. The AAD says a person can have one type for years before a second develops - skin psoriasis, then nail psoriasis, for example. It also says the type on the skin itself can change over time. Evidence
What is known
- Reasonably supported
The AAD names three documented progressions. Plaque psoriasis can develop into guttate psoriasis after an infection such as strep throat. Severe, poorly controlled plaque psoriasis can turn into erythrodermic psoriasis. And generalized pustular psoriasis can develop on top of existing plaque psoriasis, often with a trigger such as stopping a strong medication too quickly or getting strep throat.
What is uncertain
- Depends on you
The source does not say how often any of these progressions happens, and does not describe guttate psoriasis turning into plaque psoriasis as a documented direction. Most people never experience a progression toward either emergency type, so this is not, on its own, a reason for alarm.
Worth asking a clinician
My psoriasis has looked like ___ before - could this be a second type rather than the same flare?
Saving keeps this on your device and needs JavaScript, which is off in this browser.Which type do I have, and does what you are seeing match it exactly?
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Applicability check
Who was studied?
These fields show what the cited evidence reports about the people and body sites behind outcome or safety claims. “Not reported” means the reviewed source omitted the field; “Pending exact source review” means SteadySkin has not made that determination yet.
One evidence record, 2 statements
The American Academy of Dermatology calls generalized pustular psoriasis serious and life-threatening. A flare spreads pus-filled bumps across much of the skin. The person also feels very sick, sometimes with fever, headache, and muscle weakness. It states medical care is often necessary to save the person’s life. The NICE guideline calls for same-day specialist assessment when generalized pustular psoriasis is suspected.
The American Academy of Dermatology calls erythrodermic psoriasis serious and life-threatening, requiring immediate medical care. Skin over most of the body looks burnt. Signs include chills, fever, looking extremely ill, muscle weakness, a rapid pulse, and severe itch. It states most people who develop it already have another type of psoriasis. They often notice it worsening or not improving with treatment first. Hypothermia can set in quickly because damaged skin cannot regulate temperature normally. The NICE guideline calls for same-day specialist assessment when erythroderma is suspected.
- Age range
- Not reported
- Condition subtype
- Not reported
- Severity or extent
- Not reported
- Sample size
- Not reported
- Geography and care setting
- Not reported
- Skin tone or phototype
- Not reported
- Race
- Not reported
- Ethnicity
- Not reported
- Body sites
- Not reported
What that means for this page: Both sources are general patient-education and clinical-guideline material. Neither is a study of a defined population. There is no age range, sample size, or demographic breakdown to extrapolate from or restrict to. The emergency description and same-day-assessment recommendation are general, not specific to any age, skin tone, or body site.
Evidence behind this page
Sources
Each evidence badge opens the source and its limits. The full list stays available here.
- American Academy of DermatologyPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports that hair loss sometimes follows when psoriasis develops on the scalp. Supports that hair tends to regrow once the scalp psoriasis clears. Supports gently combing and brushing away scale, avoiding picking, and applying treatment directly to the scalp. Supports keeping fingernails short and smooth, alternating medicated and gentle shampoo, using conditioner every wash, and air drying instead of blow-drying. Also supports testing hair products for irritation first, and telling a dermatologist if treatment feels too harsh. Also supports telling a dermatologist if hair loss persists, since it can have other causes.
What it does not support
Does not give a byline or last-reviewed date on the page itself. Does not give a timeframe for regrowth or say every case of hair loss is caused by the psoriasis itself.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- American Academy of DermatologyPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports, per named type. Plaque: about 80% to 90% of people with psoriasis develop it. Thick raised patches with silvery-white scale. Usually on the scalp, elbows, knees, or lower back but can develop anywhere. Scratching can cause patches to thicken. Guttate: small, scaly, salmon-to-pink spots appearing suddenly on the torso, legs, arms, face, scalp, and ears. More common in children and young adults. Temporary, often clearing in weeks or months without treatment. Inverse: smooth, raw-looking red patches with little scale in the armpits, genitals, and buttock crease. Sore or painful skin. Pustular, localized: pus-filled bumps on red, swollen skin usually on the feet and hands, not infected. Can make typing or walking unbearably painful. Pustular, generalized (von Zumbusch): serious and life-threatening. A five-stage flare sequence. The person also feels very sick and may develop fever, headache, and muscle weakness. Medical care is often necessary to save the person's life. Erythrodermic: serious and life-threatening, requires immediate medical care. Skin on most of the body looks burnt. Chills, fever, looking extremely ill, muscle weakness, rapid pulse, severe itch. Most people who develop it already have another type of psoriasis. They often notice their psoriasis worsening or not improving with treatment first. Hypothermia can set in quickly. Nail: about half of people with plaque psoriasis see signs of psoriasis on their fingernails at some point. Tiny nail pits, discoloration, crumbling or rough nails, or a nail lifting away.
What it does not support
This page displays no separate revision date; the date recorded here is the calendar year checked. It does not name a separate "scalp psoriasis" type distinct from plaque, and does not give a percentage for guttate, inverse, or either pustular form. It does not say nail psoriasis is mistaken for a fungal infection, and it does not diagnose a reader.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- American Academy of DermatologyPatient education · Patient education, tier 5Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports that a person can have more than one type of psoriasis, including one type for years before a second develops. Supports psoriasis beginning on the skin before later appearing on the nails. Supports that the type on the skin can change over time. Supports three named progressions. Some people with plaque psoriasis develop guttate psoriasis after an infection such as strep throat. Some people with severe, poorly controlled plaque psoriasis see it turn into erythrodermic psoriasis. Generalized pustular psoriasis developing on top of existing plaque psoriasis often has a trigger, such as stopping a strong medication too quickly or getting strep throat.
What it does not support
This page displays no separate revision date; the date recorded here is the calendar year checked. It does not quantify how often any progression happens, and does not say guttate psoriasis becoming plaque psoriasis is a documented direction. It does not predict a course for one reader.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.
- National Institute for Health and Care ExcellenceGuideline · Regulatory / guideline, tier 1Independent source
- Published
- SteadySkin last checked
What this source can and cannot tell you
What this source supports
Supports psoriasis assessment across skin, nails, high-impact sites, life impact and joint concerns; same-day specialist assessment for generalised pustular psoriasis or erythroderma; and a treatment map that includes topical, phototherapy and systemic options.
What it does not support
It is UK guidance and does not diagnose a reader, create a US treatment sequence, determine personal urgency from a description, or establish current US labeling or coverage.
Claim-specific review for this source is still in progress. Only the source-level evidence and limits are shown here.