Recommended Dietary Allowances (RDA) for man are 900 µg and for woman 700 µg, during pregnancy the dose is slightly larger while in lactation stage is up to 1300 µg. The quantity can be also measured in international units (IU), used for the measurement of the amount of a substance. It is generally applied in biology for the measurement of vitamin dose allowances, hormones or blood products.
One thousand IU is the biological equivalent weight of 600 µg carotene or 300 µg retinol. RDA of vitamin A is 3000 IU beta-carotene or 1500 IU retinol. One Roaccutane capsule has about 5000 IU and the Roaccutane dose is prescribed towards to body weight. Typically, it's 0.5 mg of Roaccutane per kilo of body weight which is from 2 up to 5 capsules in one day. Pharmaceutical company that manufactures Roaccutane, Roche, states that it requires approximately 1 million IU retinol per day to acquire the toxic effect of more than 1 mg isotretinoin so almost 100 times lower dose is regarded as down borderline. 20,000 IU will definitely solve the most difficult cases and therefore there is no need for exaggeration. The effect would be immediately visible, even with the minimal dose.
Additional problems caused by the long-term intake arise after a period of one year, which nobody of Accutane users needed. Regardless of the security guarantee from the manufacturer, all products containing additional amount of vitamin A should be avoided. Taking too high vitamin A dose (hypervitaminosis) can result in many specific side effects such as changes and problems with the bones, skin and joints already caused by great Roaccutane dose.
