What is Substance Dependence?
This is a phrase that is used to mean different things by different people. Generally, it refers to a person whose well-being has become dependent on the use of a drug for physical reasons, emotional reasons or both.

"I’ve used so long its just normal for me. I don’t see another way.”

Substance Dependence has more specific meaning when discussed as either physical or psychological dependence.

What is Physical Dependence?
When taken on a regular basis for a period of time, some drugs will cause changes in your brain’s chemistry. Physical Dependence may result from these changes.

There are two signs that Physical Dependence has developed. The first sign is that you need to take more of a drug to achieve the same effect that you previously found from taking a smaller amount. This is Tolerance.

The second indication of Physical Dependence occurs when you try to stop taking the drug and Withdrawal Symptoms arise.

Tolerance and Withdrawal Symptoms indicate that your brain chemistry has adjusted to the regular presence of a drug in your body. Your brain now expects the substance to be present.

“I’ll never forget the first time I used. It was the first time I felt normal - warm and good - like a hug from the inside.

Then it got so I wanted that feeling all the time. It was so easy - what I had been searching for all my life was just a quick reach away - what everybody else seemed to have was always there for the taking.

When I finally tried to stop, I couldn’t. I had no idea what it would be like. Everything that I thought or felt told me to use. The pain was everywhere and all I could feel.”

Certain drugs are more likely to cause a physical dependence than others. For example, regular use of an opiate drug may result in changes in brain chemistry, tolerance and withdrawal.

It is possible to develop a Physical Dependence on a drug without being aware that this is occurring. For example, anyone who takes a benzodiazepine drug (i.e. diazepam, lorazepam, clonazepam) for sleep on a regular basis for several months is likely to develop a Physical Dependence. There will eventually be a need to increase the dose of the drug. And when you try to stop, rebound insomnia and anxiety may occur.

“I’ll never forget the first time I used. It was the first time I felt normal - warm and good - like a hug from the inside.

Then it got so I wanted that feeling all the time. It was so easy - what I had been searching for all my life was just a quick reach away - what everybody else seemed to have was always there for the taking. I knew no other way.

When I finally tried to stop, I couldn’t. I had no idea what it would be like. Everything that I thought or felt told me to use. The pain was everywhere and all I could feel.”

Physical Dependence may or may not be associated with Addiction. Physical Dependence is largely a result of taking a certain drug on a regular basis for a long time. Addiction tends to result when one is using a drug for intoxicating purposes or to chase a ‘high.’

When Physical Dependence and Addiction do occur together, the consequences may be severe and particularly tragic.

Opiate Dependence is a good example of this horrible condition. An opiate drug may first be enjoyed for the ‘high’ feeling that these drugs induce. But once used on a regular basis, changes in brain chemistry and tolerance occur. When you try to stop, terrible withdrawal symptoms occur. Fear of withdrawal feeds a deepening cycle of Addiction and further Physical Dependence.

“At first it was fun. But then I had to take more and more. I tried to stop - but I couldn’t have dreamed of a worse hell. I had no idea what I was getting myself into.”

Methadone is an example of a drug that results in a physical dependence when taken regularly. But methadone does not produce any intoxication or ‘high’ and as a result, does not fuel addiction. This unique property of methadone allows for its use to treat and alleviate severe Addiction to opiate drugs.