Opiate Tolerance

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Opiate tolerance and the subsequent withdrawal from opiates such as heroin, Morphine or other prescription painkillers has long been the center of attention when it comes to the dangers of taking these drugs.  The long term use of opiates results in tolerance, sensitization and physical dependence that can be difficult to treat and equally as difficult to overcome.  But what is it & how does a tolerance  develop?

What is it?

The National Institute on Drug Abuse defines tolerance as:

“A state in which an organism no longer responds to a drug. A higher dose is required to achieve the same effect.”

When drugs such as heroin or other opiates are used repeatedly, there is an increased risk of tolerance developing.  This tolerance will occur when the body builds up a reaction to the drug and as a result, the user must take more and more in order to produce the same effects.  The resulting tolerance will lead to a need for the user to use more often or take larger doses of the opiate in order to produce a similar affect as what was initially achieved.

If you’re struggling with opiate tolerance, call our helpline at  800-442-6158 Who Answers? to speak with a treatment adviser.

Development of Opiate Tolerance

The development of tolerance to drugs can be produced in several different ways but for the most part opiate tolerance develops in a similar manner regardless of whether the drug of choice is heroin, morphine or another opiate such as Oxycontin.  The tolerance starts at the cellular level by binding to the opiate receptors.  This triggers the release inhibited release of the adenylate cyclase enzyme which is responsible for causing the firing of various chemicals within a cell.

Sustained use or repeated use of opiates will result in the adaptation of the adenylate cyclase enzyme which causes a reduced reaction to the changes in cell firing.  The resulting effect is a diminished response to the heroin, morphine or other opiate—tolerance has developed at this point on the cellular level.  The user will feel this tolerance in the form of a lack of “high” from the drug and the perceived need to use more.

According to the British Journal of Anaesthesia, acquired opioid tolerance develops in one or more of three different ways. First, it could be a result of changes in the rate of metabolism of the drug, which results in reduced concentrations in the blood and at the sites of drug action, making the effect weaker. This is called pharmacokinetic or dispositional tolerance. The next type is called pharmacodynamic tolerance and refers to changes in systems affected by the opioid drug. An example of this is changes in receptor density which would reduce the response to the normal dose of the drug. The last way is learned tolerance, which essentially means that a user will experience reduced drug effects because they have learned to function normally in a state of intoxication. For example, one may have learned to walk a straight line despite alcohol or drug intoxication and motor impairment.

Recognizing Opioid Tolerance

Opioid tolerance does not only affect users of illicit drugs like heroin, or users who are wrongly taking prescription pain medicine, but also affects individuals who are prescribed pain medications for legitimate, chronic or temporary pain conditions. The processes that lead to this tolerance are the same in both situations and work as described above.

If you or someone you love is not feeling the effects of their dosage of pain medication as they previously had you may be developing a tolerance to the drugs. Another way this may be recognized is to see a change in your pain threshold where you will feel more pain than usual despite taking your pain medication. Similarly, if you find yourself craving larger amount of opiate drugs or need to take them more often than before, a tolerance is likely developing.

According to J.M. White and the Department of Clinical and Experimental Pharmacology, the main indicators of opiate tolerance are needing to take larger doses of the drug to feel the same effects previously experienced with less, and needing to take it more often than prescribed or than previously taken.

Is Opiate Tolerance Permanent?

Opiate tolerance develops with regular, sustained or repeated use of opiates but it is not permanent.  The only way that a tolerance to opiates will remain is to continue to take the opiates on a regular basis.  When opiate use stops for a prolonged period of time and there is time for the body to repair and get back to normal the tolerance will reduce.

The psychological tolerance that a user has on opiates is another matter.  Tolerance that develops psychologically, the perceived need to use in order to be happy and the chemical changes that occur within the brain can take quite some time to overcome.  This is not to say that the psychological tolerance that develops is a permanent factor but many opiate abusers do report having continued cravings and urges to use for many years following a major bout of opiate addiction.  Sustained and repeated opiate use can lead to a comfort in the feelings and effects of the drug that will have the user pushing the limits and doing whatever it takes to feel more and more—unfortunately, this is just part of the tolerance and addiction that begins to set in.

Reducing Opiate Tolerance

Opiate Tolerance

Getting help for opiate tolerance can give you your life back!

The only real way to reduce a tolerance to opiates is to quit using the drugs.  Opiate tolerance will continue to build with repeated use or increased doses of the drug regardless of the type of drug being used.  Reducing opiate tolerance takes time and it takes not using opiates for a sustained amount of time in order to allow the body to heal and recuperate—time is the healer of all things. Opioid tolerance is not reduced by drug replacement therapies like methadone or buprenorphine, and at this time can only be reduced through long-term abstinence from opiates.

Once you have become tolerant on opiates, abstaining from the drugs can be difficult, and it can be painful if you are rightfully taking prescription pain medication. If this is the case for you, talk to your doctor about your options. Switching to a different medication may help, or tapering off of your current medication. For illicit drug users, it may be necessary to attend a rehab program to stop using opiates, especially if you have become dependent or addicted. Rehab programs can help you detox, or rid the opiates from your body, and learn skills to help you avoid using opiate drugs.

While there is no other way yet, studies are being conducted to find ways to prevent or reduce tolerance to opioids in an effort to help individuals who legally take painkilling opiates. A study published in the US National Library of Medicine shows the promise of Agmatine for eliminating the possibility of developing morphine tolerance.

Dangers of Opioid Tolerance

There are many dangers of developing tolerance to opiates including those pertaining to the continued use of the drug, the side effect, the risk of overdose and of course the risk of addiction.  Opiate tolerance is not something to take lightly or to overlook, especially if you are prescribed opiates for the treatment of pain.  Developing a tolerance when taking the medication for pain will result in your increased perception of the pain and could lead to abusive use of the drug.

Opiate Tolerance and the Risk of Addiction

If you have been prescribed an opiate pain medication such as Morphine or Oxycontin for the treatment of chronic pain, chances are you will continue to take the medication for a sustained period of time and that tolerance will develop.  As a user, it is important that you discuss tolerance with your doctor and do not give into the temptation to use the drugs under your own terms.  Using opiates in a manner other than prescribed such as taking more than the recommended dose or taking a dose more often than recommended is considered opiate abuse and can lead to physical dependence on opiates, as well as opiate addiction.

Once you develop a tolerance to opiates, you are also likely to develop a physical dependence on the drugs. Since tolerance requires drugs to be taken more often and in higher doses, your body is becoming accustomed to having the drugs and has already experienced some changes as a result of this fact. Dependence happens when your body gets sick, or experiences withdrawal symptoms when opiates are absent for about 12 hours or more. These withdrawal symptoms may include anxiety, insomnia, irritability, runny nose, sweating, diarrhea, and more.

As your body becomes tolerant to and dependent upon opiates, addiction becomes increasingly likely. According to the World Health Organization, an addiction to opiates is characterized by changes in behavior that show an increased on drug-seeking and especially seeking drugs not for their pain-relieving effects but for their mood-altering drug effects. Some other behavioral indications of opiate addiction are denial of drug use, stealing prescriptions from others, doctor-shopping or looking to get prescribed pain medications from multiple doctors, and more. Tolerance leads to addiction because it causes increased drug use, which can often lead to physical dependence on the drugs, and psychological dependence which is closely linked to addiction.

Opioid Tolerance and the Risk of Overdose

According to the United Nations Office on Drugs and Crime, recent periods of abstinence from opiates heighten the risk of overdose. The period immediately following release from prison or an inpatient detoxification facility present significantly increased risk of overdose, as well. The reason for this is that individuals who were tolerant to opiates before entering treatment or prison likely experienced a reduction in their tolerance while they abstained from the drugs. Once out of their restrictive environments, if these individuals chose to take opiates again, their bodies would not be as accustomed to the drugs as they were prior to treatment. With respect to judgment on dosage, many individuals would not recognize their loss of tolerance and would likely take the same amount as they did previously. Due to loss of tolerance, their body would not be able to handle this amount and would experience an opiate overdose. This danger is very real for people who have stopped using opiates either by their own will, in treatment, or in jail. Opioid overdose is often fatal, and does often happen as a result of a period of abstinence which causes reduced tolerance and is followed by relapse which shocks the system.

If you suspect that you are developing a tolerance to opiates or that someone you know is opiate tolerant, call our helpline at 800-442-6158 Who Answers?  to talk with a counselor who can provide you with detailed information on the steps that you should take to prevent addiction.

Sometimes, opiates are a necessary part of a treatment regimen, especially when chronic pain is a problem, but opiate tolerance that leads to a subsequent opiate addiction is a potentially dangerous outcome that is not necessary even in the treatment of such chronic pain.  There is help available and there are other treatments for chronic pain that are less addictive and less dangerous to your overall health.

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