Cannabidiol (CBD) is a phytocannabinoid discovered in 1940. It is one of 113 identified cannabinoids in cannabis plants, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plants extract. As of 2019, clinical research on CBD included studies related to anxiety, cognition, movement disorders, and pain, but there is insufficient high-quality evidence that cannabidiol is effective for these conditions. Nevertheless, CBD is a popular herbal dietary supplement, widely promoted with unproven claims of particular therapeutic benefits. The global market size for CBD was predicted to exceed US$47 billion by 2028.Cannabidiol can be taken internally in multiple ways, including by inhaling cannabis smoke or vapor, by mouth, and as an aerosol spray into the cheek. It may be supplied as CBD oil containing only CBD as the active ingredient (excluding tetrahydrocannabinol [THC] or terpenes), CBD-dominant hemp extract oil, capsules, dried cannabis, or prescription liquid solution. CBD does not have the same psychoactivity as THC, and will negate the psychoactive effects of THC on the body if both are present. As of 2018, the mechanism of action for its biological effects has not been determined. Unlike THC, which acts on the cannabinoid receptor type 1 (CB1) as a partial agonist, CBD instead is a negative allosteric modulator of CB1 receptors.In the United States, the cannabidiol drug Epidiolex was approved by the Food and Drug Administration in 2018 for the treatment of two epilepsy disorders.
Toxic multinodular goiter (TMNG), also known as multinodular toxic goiter (MNTG), is an active multinodular goiter associated with hyperthyroidism. It is a common cause of hyperthyroidism in which there is excess production of thyroid hormones from functionally autonomous thyroid nodules, which do not require stimulation from thyroid stimulating hormone (TSH).Toxic multinodular goiter is the second most common cause of hyperthyroidism (after Graves disease) in the developed world, whereas iodine deficiency is the most common cause of hypothyroidism in developing-world countries where the population is iodine-deficient. (Decreased iodine leads to decreased thyroid hormone.) However, iodine deficiency can cause goiter (thyroid enlargement); within a goitre, nodules can develop. Risk factors for toxic multinodular goiter include individuals over 60 years of age and being female. Signs and symptoms
Symptoms of toxic multinodular goitre are similar to that of hyperthyroidism, including:
heat intolerance
muscle weakness/wasting
hyperactivity
fatigue
tremor
irritability
weight loss
osteoporosis
increased appetite
non-painful goitre (swelling of the thyroid gland)
tachycardia (high heart rate - above 100 beats per minute at rest in adults)
tracheal compression
exophthalmos

Causes
Sequence of events:
Iodine deficiency leading to decreased T4 production. Induction of thyroid cell hyperplasia due to low levels of T4. This accounts for the multinodular goitre appearance. Increased replication predisposes to a risk of mutation in the TSH receptor. If the mutated TSH receptor is constitutively active, it would then become toxic and produces excess T3/T4 leading to hyperthyroidism. Diagnosis
Treatments
Toxic multinodular goiter can be treated with antithyroid medications such as propylthiouracil or methimazole, radioactive iodine, or with surgery. Another treatment option is injection of ethanol into the nodules.