You’re absolutely sure that a mole that you’ve always had has suddenly gotten bigger and also turned reddish in a matter of a day or two.

Melanoma or what can this be?

Most Likely Causes of a Mole Suddenly Getting Bigger and Red

First off, what appears to be a sudden increase in size of a mole does NOT mean that the number of melanocytes has increased.

Melanocytes are the pigment cells that comprise common moles. These specialized cells are packed together and hence, appear as a brown, tan or beige spot.

What may cause a benign mole to look bigger and redder are any of the following, says Sharyn Laughlin, MD:

• A nearby rash

• Nearby dermatitis from an irritant

• Psoriasis

• Eczema

• Acne nearby

• A pustule beneath the mole

• An insect bite at the mole

“Trauma, rash, irritation and/or hormonal factors can all cause these sudden changes,” says Dr. Laughlin, a dermatologist and developer of the DermaEnvy Skincare ™ line of sun protection products and medical director of Laserderm, a pioneering laser skin surgery clinic in Ottawa, Ontario, Canada.

It is extremely unlikely that melanoma could cause a mole to suddenly get larger and turn red overnight.

The “suddenly” here refers to literally a visible change in size over a matter of days (or even under 24 hours), and a conversion to red or a red tinge also in a matter of a few days.

These fast and visible changes are not consistent with melanoma.

Dr. Laughlin explains, “You would assess for potential causes like scratching or rubbing, and take into account things like hormonal changes, e.g., going on or off the birth control pill, pregnancy, menopause, starting or stopping hormonal replacement therapy, a growth spurt around puberty, and men who may be on estrogenic-like drugs for prostate cancer or male pattern alopecia.

“An ingrown hair can also cause a folliculitis that produces the swelling and redness within the mole.”

Melanoma typically causes moles to increase in size — but not over a period of days visible to the naked eye. Color changes such as red, as well, would not occur over a period of days.

Nevertheless, Dr. Laughlin says to “watch to see if things persist over the three month period.”

Keep track of the mole to see if it just keeps getting bigger and bigger, and especially if other changes are beginning to appear such as a loss of symmetry or a bleeding of its pigment into surrounding skin.

If you’re concerned, even if there are no additional changes in appearance, request that your dermatologist perform a biopsy.

For more information on a mole quickly turning red and appearing a little bigger than usual, read what happened to me.

In practice for 30+ years, Dr. Laughlin has been lead or co-investigator in many research trials and an innovator in developing new laser technology.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  


Top image: Shutterstock/dean bertoncelj