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Doctor insights on: How Long Does Sunscreen Last Once Applied

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Skin care: how long does sunscreen last?

Skin care: how long does sunscreen last?

At most 2 hours: Although the spf rating of a sunscreen tells you how effective it is during use, it is important to reapply frequently and in adequate amount. Sunscreen should be reapplied every 2 hours to maintain efficacy, as factors such as sweating, water exposure, and physical removal can decrease its effect and lead to burns and skin cancer risk. ...Read more

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When applied on the skin, how long does my sunscreen work for? Does it vary?

When applied on the skin, how long does my sunscreen work for? Does it vary?

Varies: Based on activity and sweating. But generally it should last couple hours in active sun exposure. If just as protection for the day to day activities than one to two applications per day should be effective. ...Read more

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How long is sunscreen good for, if it has been two years past the expiry date?

How long is sunscreen good for, if it has been two years past the expiry date?

Sunscreen: As an absolute efficacy endpoint, it is probably not good one year after it expires. Practically speaking though, and because it is so cheap and effective when used properly in the prevention of skin cancer, buy a new one to start the season. By the way, I just saw a report that 5+ blistering sunburns IN YOUR LIFETIME, increases skin cancer risks. So, lather up with lotion!!! ...Read more

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I use some sunscreen that has 15 hrs long effect, they said that I don't have to reapply. So what do you think?

I use some sunscreen that has 15 hrs long effect, they said that I don't have to reapply. So what do you think?

Doubtful: I would be very doubtful that this is really true. No sunscreen is waterproof they are only water resistant. ...Read more

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How long after the expiry date is sunscreen still useable for? I have some that says it expired March 2014. Is it still OK to use?

How long after the expiry date is sunscreen still useable for? I have some that says it expired March 2014. Is it still OK to use?

Answer below.: Is sunscreen from last year still good? When does sunscreen expire?
Answers from Lawrence E. Gibson, M.D.

Sunscreens are designed to remain at original strength for up to three years. This means that you can use leftover sunscreen from one year to the next.

http://www. Mayoclinic. Org/healthy-living/adult-health/expert-answers/sunscreen-expire/faq-20057957 ...Read more

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I burn easily and the last time I used sunscreen (SPF 30) my whole back was burnt and I developed a fever. Do I need to go get a specialized sunscreen?

I burn easily and the last time I used sunscreen (SPF 30) my whole back was burnt and I developed a fever. Do I need to go get a specialized sunscreen?

Re-Apply hourly: SPF30 is good usually higher number no much better. But if your skin is very sensitive best is to wear " Sun protective clothing". Otherwise re apply Sunscreen every hour. Avoid sun exposure in peak hours 11AM-3PM. Also keep well hydrated with water. If you have some suspicious lesion on skin - see your doctor. ...Read more

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What will happen if I stop using nadilona fade cream because my 3 yr old scar has finally disappeared? 2. How long will I have to use sunscreen?

What will happen if I stop using nadilona fade cream because my 3 yr old scar has finally disappeared? 2. How long will I have to use sunscreen?

O.K. to stop: If scar has faded, just protect from sun indefinitely with high spf sunscreen. Can use fade cream again if it darkens despite this. ...Read more

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I've been at the beach for the last couple of days, wearing sunscreen with only zinc and titanium active ingredients, but my skin now itches. Why?

I've been at the beach for the last couple of days, wearing sunscreen with only zinc and titanium active ingredients, but my skin now itches. Why?

Inflammation: Hi. These sorts of skin reactions can happen with any sort of inflammatory process. You could simply be dried out from the beautiful sun and cool breezes. (I'm jealous). Or you might actually be sensitive to the topical agents that you've used (even though you may think that you shouldn't be). Everybody is different in this regard. Use some sort of hypoallergenic cream and hydrate with H20! ...Read more

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For the past5 summers I break out in little liquid filled itchy bumps on my arms. I wear sunscreen when outside for prolonged time. Is this sun?

For the past5 summers I break out in little liquid filled itchy bumps on my arms. I wear sunscreen when outside for prolonged time. Is this sun?

Contact allergy?: Itchy, fluid-filled bumps are classically seen in contact dermatitis. A common example would be poison ivy. Many chemicals can cause this reaction, even those in sunscreen. The sun itself can cause different kinds of rashes, but would rarely cause the symptoms you describe. See a dermatologist or allergist about your rash, and take a picture of it in case it goes away before your appointment. ...Read more

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I have allergic dermatitis. Last month during vacation sunbathed w/ one eczema w/ sunscreen. The rash is gone but the skin is lighter. Is it normal?

I have allergic dermatitis. Last month during vacation sunbathed w/ one eczema w/ sunscreen. The rash is gone but the skin is lighter. Is it normal?

Yes: Sun exposure can decrease the severity of eczema. However, chronic exposure to the sun with or without sun burn can increase sun damage (not visible to the naked eye) and that can later lead to skin cancer. Ask your dermatologist or md for good moisturizer recommendations and for topical steroid oil or cream recommendations. This is safer that long term tanning for your eczema. ...Read more

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I don't know if it is a allergic reaction to the sun or my sunscreen but every time I go out for a long time in the sun I get scratchy bumps that sting a lot and I usually have to stay the rest or the day in my bed?

I don't know if it is a allergic reaction to the sun or my sunscreen but every time I go out for a long time in the sun I get scratchy bumps that sting a lot and I usually have to stay the rest or the day in my bed?

? solar urticaria: Yes, there is such thing, allergy to sun rays, you may want to avoid sun exposure from 10 am -4 pm, limit exposure if you have to, use heavy sun screen UPF > 50, that if u have to stay outdoors, also 2nd generation OTC antihistamines taken regularly, will help, you need evaluation hy an allergist/dermatologist as other treatment modalities with correct diagnosis, like phototherapy, are available, ...Read more

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Any kind of sun exposure & my forehead breaks out in a rash hives. Iput sunscreen on. I have only had the problem for the last 3yr no chge skin product?

Any kind of sun exposure & my forehead breaks out in a rash hives. Iput sunscreen on. I have only had the problem for the last 3yr no chge skin product?

? Solar urticaria: Or photosensitivity if on certain medications, avoid sun exposure as much as you can, sun screen is wise to use to avoid accidental exposure, OTC first generation antihistaminic as diphenhydramine can help reduce hives and itching, please check with a dermatologist / allergist for management, and possibly desensitization ...Read more

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Is it common to be allergic to sunscreen? Raised red rash over legs that itch. Also itchy behind ears. Rash/itch last 1-2 weeks. Or is it UV sensitive

Is it common to be allergic to sunscreen? Raised red rash over legs that itch. Also itchy behind ears. Rash/itch last 1-2 weeks. Or is it UV sensitive

Could be allergy!: If the rash appears after applying sunscreen cream, it is likely due to allergy to the product. Though not common, you could develop a sensitivity to any cream. ...Read more

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During my last two florida visits, I experienced a hive like rash on my arms and partially on my neck. The sunscreen was 50 spf containing zinc oxide, octinoxate, octisalate. I had to use a derm ointment topically and take an antihistimine to relieve symp

Photoallergic: Paradoxically, some ingredients in sunscreen other than titanium or zinc can cause an allergic reaction after interacting with sunlight. You may need to find an alternative with different ingredients. Another possibility is that you are taking a drug which make you sensitized to the sun and thus hives only at exposed areas. ...Read more

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Does sunscreen expire?

Does sunscreen expire?

Yes: Sunscreens have a shelf life of three years. After this, they start to lose their stability and efficacy. You should see an expiration date on your bottle of sunscreen and should use it before that date. If you don't see an expiration date, write the month and year you purchased it on the bottle and toss after three years. Do not use any sunscreen that has become lumpy or has turned an odd color. ...Read more

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What is the best sunscreen?

Sunscreen: The best sunscreen should have a molecule that protects against UVB & UVA (UVA-2 and UVA-1). Zinc Oxide is the molecule that has the ability to block UVA & UVB. So when considering using a sunscreen, look for Zinc Oxide. ...Read more

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What sunscreens do you recommend?

What sunscreens do you recommend?

Neutrogena, Alta MD: The neutrogena helioplex and the anthelios by la roche posay are my favorites. For acne prone skin, the alta md uv clear works well. It is important to use sunscreens with both uva and uvb coverage. Spf value refers to uvb protection. The new fda ruling requires uva protection labeling, which will be presented as + (lowest), ++, or +++ (highest). Reapply every 2 hours while in the sun. ...Read more

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Are Asian sunscreens safe to use?

Are Asian sunscreens safe to use?

Sunscreen: There can't be a gross generalisation about whether a sunscreen from Asia is good or bad. Stick with a reputable brand. ...Read more

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Should I wear sunscreen everyday?

Should I wear sunscreen everyday?

Yes: Even while your driving in a car sun still can do damage, skin seuticuals has a spf 50 I highly recommend
see your dermatologist or plastic surgeon to purchase it. ...Read more

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How does sunscreen actually work?

How does sunscreen actually work?

Sunscreen: Sunscreen combines organic and inorganic chemicals to filter the light from the sun so that less of it reaches the deeper layers of your skin. Like a screen door, some light penetrates, but not as much as if the door wasn't present. Sunblock, on the other hand, reflects or scatters the light away so that it doesn't reach the skin at all. ...Read more

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What is the best sunscreen to use?

What is the best sunscreen to use?

Zinc oxide: Many of the sunscreens available in the us are banned in europe due to concerns about carcinogenic risk of some of the ingredients. However, the risk of skin cancer after a sunburn far exceeds any potential risk from sunscreens. The safest sunscreens are the barrier sunscreens containing zinc oxide or titanium. ...Read more

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What makes sunscreen so important? |

Skin Cancer: Sunscreens protect your skin from the harmful uv rays of the sun. In addition to damaging the quality of the skin, they can cause cancers to develop. I recommend the physical blocks (zinc and titanium) because they have a very good safety profile and work very effectively. If you are going to be in the sun - use a minimum of SPF 15 - follow product directions. ...Read more

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Should I use a special sunscreen?   

Not really: The fda has recommended that the term sunblock be dropped as it is often very misleading and can result in patients believing they have more protection from the sun than they actually do. I agree, a good sunscreen with an spf of 50, that contains both a uvb protector and a metal such as zinc or titanium oxide for uva. That's all you need if you reapply it frequently. ...Read more

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Does more SPF mean better sunscreen?

Does more SPF mean better sunscreen?

Yes and no: 30 is better than 15, but anything over 30 is probably marketing hype rather than any true benefit. ...Read more

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What should I look for in a sunscreen?

What should I look for in a sunscreen?

2 things: You need 2 things: a good uvb protector. This is what the spf rating refers to. Octinoxate is wonderful and safe. No more than a 50 spf. Anything higher is useless and to full of other chemicals. You must have a metal in it such as zinc or titanium. These protect against uva rays. Higher spf is nonsense. You must reapply them frequently and avoid the sun to be affective. Wear a hat and be well! ...Read more