While NAC differs from NAD+, it supports cellular energy indirectly by boosting glutathione production
p53 tumour-suppressor caution Because FOXO4-DRI intervenes in the p53 pathway, which is critical for tumour suppression, there is theoretical concern that interfering with p53 dynamics might carry oncogenic risk

Notes: Acute tolerance (a reduction in response for a given dose) develops rapidly (less than 1 hour), but not at the same rate for different physiologic effects (skin temperature, heart rate, subjective effects) Withdrawal symptoms such as cigarette craving can be reduced in most individuals by plasma nicotine levels lower than those from smoking Withdrawal from nicotine in addicted individuals can be characterized by craving, nervousness, restlessness, irritability, mood lability, anxiety, drowsiness, sleep disturbances, impaired concentration, increased appetite, minor somatic complaints (headache, myalgia, constipation, fatigue), and weight gain References: Belkoniene M et al (2019): Near fatal intoxication by nicotine and propylene glycol injection: a case report of an e-liquid poisoning
If you feel any pain then use the painkillers or consult the doctor
Taking a supplement at the wrong time can sometimes limit its effectiveness
Leslie Baumann says in her great Cosmetic Dermatology book that thanks to the unique molecular characteristic of Sodium Cocoyl Isethionate, it "has defined a new dimension in the mildness of cleansing bars "