When people say they are allergic to something or that they are suffering from an allergy, they are actually referring to several inflictions instead of a single problem. An allergy is caused when your immune system reacts to an alien object or chemical in your body. This reaction if often not supposed to take place. The alien objects that enter your body can be found the following forms –

• dust
• chemicals from the household like cleansers, chlorine, soaps, paints, etc
• pollen
• some types of nuts
• citrus fruits
• some seafood varieties
• animal hair shed from pets
• pollutants from car and industrial emissions
• inhalation of smoke from fire
• some medications and so on

continue reading Natural, Simple Ways to Prevent or Reduce Allergies

WHAT IS LASER EYE SURGERY?

Refractive or Laser Eye Surgery (LES) is a laser reshaping of cornea thus changing its focusing power (1), (pictures 1,2). For patients with moderate refractive errors this ambulatory procedure is a quick way to get free of glasses or contact lenses.

Picture 1. Eye doctor performing laser eye surgery
(source: whmc.af.mil)

COST OF LASER EYE SURGERY 

The cost of LES can vary widely but it is rarely under $1,000 per eye (2).

REFRACTIVE ERRORS TO CORRECT WITH LES

The light from an observed object penetrates through the cornea, lens and viscose liquid of the eye globe, refracts, and focuses on retina as an image. In farsightedness - hyperopia the eye globe is too short, and since the lens cannot refract the light from near objects enough, the light will fall behind retina and give a blurred image. In presbyopia (farsightedness of the aged) the lens becomes rigid and cannot refract the light from near objects efficiently, so it will  again focus behind the retina. In nearsightedness (myopia), the eye globe is too long and light from distant objects will focus in front of the retina, so images of distant objects will be blurred. In astigmatism blurred vision is caused by irregularities in the corneal or lens shape (3). All mentioned refractive errors can be corrected with laser eye surgery.

continue reading Corrective Laser Eye Surgery

Hair Dye Allergies – Introduction

About 5% of permanent hair dyes users develop allergy, mostly as an allergic contact dermatitis with redness and itching in the head area, but systemic reaction with involvement of the whole body skin and other organs may appear in severe cases (1). Hand dermatitis affects considerable percent of hair-dressers (2). The main cause is substance PPD.

PPD (4-ParaPhenyleneDiamine, C6H8N2)

PPD is widely present on the market since 1909 and it is still used in over 2/3 of permanent hair dyes. Commercial hair dye product typically comes in two bottles: the one with PPD based dye (non-oxidized and thus colorless) and the other with oxidizer or developer, usually hydrogen peroxide (H2O2). In the hair dying process initially the peroxide is used to break down the natural hair pigment melanin, and then the PPD is used to replace melanin. When PPD reacts with peroxide it becomes partly oxidized and colored and it is this form which may cause allergy. Fully oxidized PPD does not cause allergy, so PPD sensitive persons can wear fur coats dyed with PPD safely (3). PPD can also be found in some dark colored cosmetics and temporary tattoos. In France, Germany and Sweden PPD was banned as a hair dye because it was thought to be too dangerous for health. (4).

Alternative names for PPD: PPDA, Orsin, Rodol, Ursol.

continue reading Hair Dye Allergies