Originally Posted by
Sally1009 
Btw what does cross tolerant?
Cross-tolerance means that when you develop a tolerance to a drug, you will also have a tolerance to other closely related drugs. This also means that you can use one drug to stave off the withdrawal from another, provided they are cross-tolerant. For example, methadone can be used to counter heroin withdrawal. Likewise, benzodiazepines (like Librium) can be used to counter alcohol withdrawal, which is why they are used for detox. The more closely related two drugs are, the stronger the cross tolerance effect will be.