Your skin might be affected by acanthosis nigricans which is identified by dark patches, even on the throat and joints. Being overweight and having high blood pressure are risk factors for this. The treatment is to lose weight and control the BP, as a result, the patches can be healed. Follow a healthy diet, exercise regularly, and be consistent with your prescribed medications to control your blood pressure.

Pigmentation is not treated quickly. It takes a while for treatments to work. But you can visit a dermatologist and discuss this. Based on your particular condition, he may suggest some alternative treatments that may work for you like chemical peels, laser treatments, topical creams etc. Hope this helps. 

Your symptoms sound like athlete’s foot and toenail fungus. An athlete’s foot can cause your nails to turn yellow, make the skin on your feet peel off, and make your toes hurt. The fungus that leads to athlete’s foot loves warm, damp areas – like sweaty feet. You can use over-the-counter antifungal creams on your skin and nails to treat it. Also, try to keep your feet clean and dry so they are less appealing to the fungus.

Acne is multi-factorial problem, hormonal disease in most of the patients, diet, exercise, hygiene, grooming practices play important role.so visiting dermatologist and taking treatment is one option and maintain treatment for long time because if you are getting any improvement with the treatment then continue it otherwise dermatologist will change it. there are few things that has to be taken care. One thing not to apply hair oil, avoid having dandruff or use anti-dandruff shampoos weekly on the scalp, using face washes that have salicylic acid or glycolic acid. Avoid using thick greasy moisturizers or cream on the face. Use only creams that are gel based or water based. Drink plenty of water, avoid fat or cheesy diet, exercise 10-15 mins of the day. Topical steroids have to be avoided. Topical antibiotics like Clindamycin are useful. Oral Antibiotics or retinoids are advised. 

Nose pie­rcings sometimes get infe­cted. Redness, swe­lling, pus appear when germs e­nter. Soframycin ointment doesn't tre­at piercing infections. Saline solution (saltwate­r) gently cleans the are­a. Rinse piercing multiple time­s daily. If symptoms persist beyond seve­ral days, consult a doctor. Avoid over-the-counter antibiotic cre­ams; they aren't effe­ctive for piercings. 

The skin will quickly heal but, in the process, it may develop some marks. The skin appears normal at first but later the burn marks appear. To help the marks fade, you can buy a cream from the pharmacy that contains either vitamin E or aloe vera. They can be of help in the healing process and also, they can make the marks less visible.

You are likely experiencing a heat rash and chafing in your private areas. This usually happens because perspiration becomes trapped against the skin thereby irritating. Signs may include redness, itching, and sometimes little bumps. To assist with this, tighten any loose-fitting clothes, stay cool, and ensure it’s dry down there. Apply some soothing ointment and be sure to take breaks if possible.