Final answer:
Treatments that can cause hyperpigmentation, hypopigmentation, and sensitivity include desensitization therapy and improper exposure to UV rays. These effects can also be indicative of underlying health issues such as autoimmune diseases or genetic conditions like xeroderma pigmentosum.
Step-by-step explanation:
Treatment methods that may lead to hyperpigmentation, hypopigmentation, and/or sensitivity if administered improperly include various dermatological procedures and therapies. One example is desensitization therapy for allergies, which involves repeated injections of allergens and if not properly conducted, could lead to such skin reactions. Another example is exposure to UV radiation during tanning or without proper protection, which can result in sunburn, hyperpigmentation, and increased risk for skin cancer.
A treatment such as desensitization therapy must be monitored to prevent severe systemic reactions, with medical staff ready to provide resuscitation and drug treatment. Extreme UV exposure also has the acute effect of suppressing the immune system.
Certain autoimmune diseases, like Addison's disease, may manifest as hyperpigmentation. However, when discussing hyperpigmentation related to treatment, skin conditions like xeroderma pigmentosum due to UV sensitivity should be recognized. The text mentions that UV rays can cause skin lesions and an increased likelihood of skin cancer due to the suppression of the immune system. Precautions include using sunscreen and limiting exposure to UV rays.