One of the more surprising things people on chlorpromazine sometimes discover is that an hour at the beach leaves them with a deep red sunburn that would normally have taken much longer. The phenomenon has a name — drug-induced photosensitivity — and it is both well-documented and entirely manageable once you know about it. The same effect can occur on other phenothiazines and, less commonly, on a handful of other antipsychotics. It is worth understanding because the consequences range from painful burns to long-term skin pigmentation changes and increased skin cancer risk.
Several antipsychotics — most notably chlorpromazine and other phenothiazines — make skin react more strongly to ultraviolet light, producing severe sunburns and longer-term pigmentation changes that are entirely preventable with sun protection.
Two kinds of photosensitivity
Drug-induced photosensitivity comes in two flavours, and both can occur with antipsychotics:
- Phototoxic reactions — the medication absorbs ultraviolet light and produces molecules that damage skin cells directly. Looks like a severe sunburn, often within hours of sun exposure. Dose-dependent.
- Photoallergic reactions — the medication-plus-light combination triggers an immune response. Looks like an itchy eczema-like rash, often delayed by 24 to 72 hours. Not strictly dose-dependent.
The FDA's consumer guidance on drugs and sun sensitivity describes the same two patterns and lists antipsychotics among the drug classes most often involved.
Which antipsychotics are most photosensitising
- Phenothiazines — chlorpromazine in particular, but also perphenazine, trifluoperazine, fluphenazine, and the historical thioridazine. Chlorpromazine is the classic example and can cause both phototoxic burns and a slate-grey or purple skin discolouration after long-term high-dose use.
- Thioxanthenes like thiothixene — modest risk.
- Clozapine and olanzapine — uncommon reports.
- Risperidone, aripiprazole, quetiapine, lurasidone — rarely associated.
Many other commonly co-prescribed medications are also photosensitising: tetracycline antibiotics (doxycycline), some thiazide diuretics, some NSAIDs, hydrochlorothiazide, voriconazole, and others. The combined effect can be substantial.
What it looks and feels like
- Severe redness, burning, or stinging in sun-exposed areas — face, neck, hands, forearms, the V of the chest
- Onset within hours (phototoxic) or 1–3 days (photoallergic)
- Sometimes blistering
- Itchy rash in photoallergic reactions
- Long-term: bluish-grey or purple discolouration of sun-exposed skin (chlorpromazine, after years)
Practical prevention
Sunscreen done seriously
- Use a broad-spectrum sunscreen (UVA and UVB) with SPF 30 or higher, every day
- Reapply every 2 hours and after swimming or sweating
- Mineral sunscreens (zinc oxide, titanium dioxide) are particularly effective and well tolerated
- Do not forget ears, neck, scalp (if hair is thin), backs of hands, and tops of feet
Clothing and timing
- Long sleeves, wide-brimmed hat, and UV-protective sunglasses make a substantial difference
- Avoid sun between 10 a.m. and 4 p.m. when UV is strongest
- UV penetrates clouds and car windows — protection is needed even on overcast days
- UPF-rated clothing is widely available and useful for outdoor work
Be cautious with windows and reflections
Driving for long periods can cause one-sided sun damage; tinted windows or sun sleeves help. Snow, water, and sand reflect UV strongly.
Vitamin D
If you avoid sun deliberately, ask your prescriber about vitamin D status. Many people with schizophrenia are vitamin D deficient, and supplementation is often appropriate. See our article on vitamin D and schizophrenia.
If a reaction has already happened
- Cool compresses and aloe-based gels reduce burning
- Over-the-counter pain relievers help with discomfort
- For more severe reactions, your clinician may prescribe topical or oral corticosteroids
- Drink plenty of fluids; severe sunburns are dehydrating
- Avoid further sun exposure until healed
You have widespread blistering, fever, severe pain, swelling that crosses joints, or signs of infection (pus, spreading redness). Severe drug-related sun reactions sometimes need medical management.
The chlorpromazine pigmentation question
Long-term high-dose chlorpromazine — particularly historical doses of several hundred mg per day for many years — has been associated with a distinctive bluish-grey or purplish skin discolouration in sun-exposed areas, and similar deposits in the eye. Modern doses are lower and the syndrome is less common today, but it remains a recognised long-term effect. Sun protection from the start is the cleanest prevention.
The big picture
Photosensitivity from antipsychotics is one of the easier side effects to prevent and one of the more annoying to deal with after the fact. It does not mean you have to live indoors. It means making sun protection a daily, automatic habit — sunscreen on the bathroom counter, a hat by the door, sunglasses in the bag. People who do this from day one of their phenothiazine treatment generally never have a serious problem. The sunburn lesson is one most patients only have to learn once.
This article is for educational purposes only and is not medical advice, diagnosis, or treatment. Always consult a qualified mental health professional. If you or someone you know is in crisis, call or text 988 in the US, or your local emergency number.