Brief Answer:
lifestyle changes, self help, doctor's advise.

Detailed Answer:
Hi Moorehornet,
Thanks for the query.
In these days of struggle for success, first impression/ personality matter much, I understand your concern.
Blackening of lips can be caused by many causes ,ranging from some health conditions to life style factors.Let us enlist them in short & sort out one by one.
* Color of lips depends on natural melanin pigment you have. Dark people find it darker as age advances.
*Habit of constant biting /licking of lips- Needs to be changed. Keep the lips moist by drinking more water/ moisturizers.
*Exposure to sun/allergic reaction.( cosmetics or tooth paste)
*Eating disorders like anorexia/ acid reflux-GERD may cause repeated contact of lips with gastric acid- cause the dark lips.- Needs treatment.
* Nutrition-
- Anemia-less iron leads to less oxygenation of blood & lips may turn bluish
- Excess iron in blood turn lips black.
- B complex deficiency can lead to repeated cracks of lips ,which turn black on healing.
* health problems due to heart/ respiratory problems may cause blue/ black lips due to less oxygenated blood circulates in body.
* Life style -
- Smoking cigarette for long time .
- alcohol abuse,regular narcotic use (Crack cocaine/Crystal meth users )
-Betel leaf/Tobacco users
* Use of certain medicines- Tetracyclins,antimalerials,antidepressants,skin lightening agents,Photosensitive drugs for skin dis orders Can lead to dark lips.

Management- It consists of-
* controlling basic cause by self determination/ doctor's advise.
- Be well hydrated, have a healthy diet with optimum iron.vitamin A,C,E,B complex.,
- Change life style, leave hazardous habits of smoking, drinking, indulging with drugs.
- Leave lip biting/licking habit,
-Apply lemon juice + honey to lips ( natural bleaching)
- Regular lip care-cleaning, massage with olive oil. application of Aloe vera helps., butter, cleared butter Thick cold creams
* consult a physician for excluding cardiac,respiratory, iron, B complex problems.Start treatment as per need.
Check with the drugs causing it,& get them changed if needful.
* Yes for time being you can hide it with make up/lipstick- check that you are not allergic to it.
I hope, I have answered you up to your satisfaction. Any follow up query is welcome.
Thanks.

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