Mu Opioid Receptor

Found on the membrane of nerve cells, mu opioid receptors acts as a ‘middle-man’ to opioid analgesia, opioid tolerance and addiction. The Mu Opioid Receptor, often referred to as MOR, plays a important role in addiction process. As a member of the opioid receptor family, it is primarily found in the brain and spinal cord. To put it simply, this receptor is responsible for the effects of opioid drugs, both prescribed and illicit, on your body.

When opioids attach to the Mu Opioid Receptor, they activate a chain of events that result in pain relief, sedation and even feelings of euphoria. This provides an explanation for why opioids can be highly addictive. Over time, your body becomes dependent on these opioids and cravings for the drugs can become overpowering.

Understanding the Mu Opioid Receptor is fundamental for addiction treatment. Medications like methadone, buprenorphine and naloxone are used to target this receptor, helping to manage withdrawal symptoms and reduce cravings. By blocking the Mu Opioid Receptor, these medications can aid in the recovery process by alleviating discomfort and reducing the risk of relapse.

The Mu Opioid Receptor is not a recent discovery. It was identified and characterised back in the 1970s. Since then, scientists have continued to study this receptor to gain a better understanding of its function and develop more effective treatments for addiction.

Tolerance and Physical Dependence

Physical dependence can develop after 2 to 10 days of continuous opioid use with abrupt cessation leading to withdrawal syndrome. This syndrome, as per the ICD-10, is a group of symptoms emerging from the withdrawal of a substance after prolonged or high-dose use. Withdrawal symptoms include physiological disturbances and clinical manifestations like pain, autonomic symptoms (diarrhea, rhinorrhea, diaphoresis), central nervous system effects (sleeplessness, restlessness, tremors) and strong medication cravings. Addiction, a potential outcome of drug dependence, is marked by psychological and behavioural symptoms, including compulsive use and a high tendency to relapse after withdrawal.

Tolerance mechanisms show that high doses of opioids can lead to MOR (and DOR) internalization, necessitating greater opioid intake for the same effect due to fewer receptors. When opioids are removed (e.g., using an antagonist), the endogenous opioids fail to activate the remaining receptors.

Opioid therapy using MOR agonists raises concerns due to the potential for developing tolerance and physical dependence. Tolerance occurs when consistent stimulation of the MORs requires increasingly higher doses to achieve the same effect. In cancer patients receiving pain treatment, this tolerance is often due to escalating pain levels rather than the drugs themselves. Understanding the mechanisms behind tolerance and dependence is fundamental for managing opioid therapy effectively and developing new treatments. Research, including in vitro mutagenesis and receptor chimera analysis, focuses on specific domains and amino acid residues of the MOR to understand its function better.

    Addiction & Mental Health

    Treatment Services

    Founded in 2008, WeDoRecover has evolved from an advisory service for addiction treatment into a comprehensive provider of care, following its 2019 merger with Changes Addiction Rehab in Johannesburg. Specialising in connecting patients to top-tier addiction treatment centers in the UK, South Africa and Thailand, WeDoRecover supports individuals globally, including those from the United Arab Emirates and Europe. Accepting both South African medical aid and international health insurance our organisation facilitates access to high-quality treatment for substance and alcohol use disorders, offering individualised care that addresses the physical, mental and social needs of patients.

    Our team, led by Gareth Carter, offers empathetic and professional support, guiding you through every step of the treatment process. Whether you're in South Africa or abroad, our acceptance of various insurance plans makes quality care accessible, providing a platform for lasting recovery and a healthier future.

    Inpatient Rehab

    Rehab care is a good option if you are at risk of experiencing strong withdrawal symptoms when you try stop a substance. This option would also be recommended if you have experienced recurrent relapses or if you have tried a less-intensive treatment without success.


    If you're committed to your sobriety but cannot take a break from your daily duties for an inpatient program. Outpatient rehab treatment might suit you well if you are looking for a less restricted format for addiction treatment or simply need help with mental health.


    Therapy can be good step towards healing and self-discovery. If you need support without disrupting your routine, therapy offers a flexible solution for anyone wishing to enhance their mental well-being or work through personal issues in a supportive, confidential environment.

    Mental Health

    Are you having persistent feelings of being swamped, sad or have sudden surges of anger or intense emotional outbursts? These are warning signs of unresolved trauma mental health. A simple assesment by a mental health expert could provide valuable insights into your recovery.

    Finding the right rehab close to you is simple with WeDoRecover. Our network includes the finest rehab centers, ensuring personalised, quality care for your recovery needs. Let Gareth Carter and our empathetic team help guide you to a center that feels right for you, offering expert care and support. Start your healing today by choosing a rehab that's not just close to you, but also that truly cares about your loved ones recovery.

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