How many days will it take that marijuana and cigarette not be founded in ct scan for head, the reason for the ct scan is b/c of headache (migraine)?

2 risky habits. You cigarette habit may cause white matter lesions in the brain, which will not disappear, but marijuana does not seem to cause this, but in adolescents there is a lingering question of some degree of brain atrophy. Actually, migraine headaches, in some, may respond to cannabinoids. Let your doctor know about these 2 habits.
Not seen in CT scan. CT scan will not show residuals of cigarettes containing tobacco or marijuana, but will show some causes of migraine and head pain. Urine or blood tests will show the THC. Discuss their effects regarding your migraines with your treating doc to determine if lifestyle changes can improve your condition.