Theoretically, if the medication is in the same dosage, the effects of an extended-release tablet and a controlled-release tablet should be the same, with only slight differences in the rate of release and use of the medication. Under normal circumstances, extended-release tablets release the drug slowly at a non-constant rate, which prolongs the release time of the drug in the body and enables the drug in the blood to maintain an effective blood concentration for a longer period of time. Controlled-release tablets, on the other hand, generally release the drug at a slow constant rate or near constant rate, which maintains a constant blood level, is more stable, and allows the drug to work for a longer period of time. In addition, care should be taken when using controlled-release tablets drugs, the drug can not be broken open to take, because the controlled-release tablets in the production, will form a kind of controlled-release membrane or controlled-release skeleton, the drug will be broken open will destroy it, the drug may be released rapidly, and in serious cases, may also cause drug poisoning. However, extended-release tablets can generally be broken open and used in the clinic, only the dose is reduced and the effect of the drug is relatively small. Whether you take extended-release tablets or controlled-release tablets, they should be taken under the guidance of a medical professional to avoid adverse consequences.