Understanding Substance Use Disorders
Substance use disorder (SUD) is a clinical term that encompasses a range of conditions involving the problematic use of alcohol, illicit drugs, prescription medications, or other psychoactive substances. The term replaces older labels such as "substance abuse" and "substance dependence" in the DSM-5, reflecting a dimensional understanding of the condition on a spectrum from mild to severe.
Addiction — the severe end of the substance use disorder spectrum — is characterised by compulsive substance use despite harmful consequences, loss of control over use, and significant impairment in daily functioning. It is recognised by major medical bodies as a chronic brain disorder involving neurobiological changes in reward, motivation, memory, and inhibitory control systems.
South Africa has among the highest rates of substance use disorders in Africa. The South African Community Epidemiology Network on Drug Use (SACENDU) monitors substance use trends nationally and consistently reports high rates of alcohol, methamphetamine, cannabis, and heroin use.
Substances Commonly Misused in South Africa
Alcohol
Alcohol is by far the most widely misused substance in South Africa. The country has one of the highest per capita alcohol consumption rates in the world among drinkers. Alcohol use disorder is associated with liver disease, cardiovascular disease, neurological damage, mental health problems, road accidents, violence, and family breakdown. Foetal Alcohol Spectrum Disorder (FASD), caused by alcohol use during pregnancy, affects an estimated 6–9% of children in some Western Cape communities — among the highest rates globally.
Methamphetamine (Tik)
Tik (crystal methamphetamine) is a highly addictive stimulant that is particularly prevalent in the Western Cape, where South Africa has among the highest methamphetamine use rates in the world. Tik produces intense euphoria followed by severe crashes, and its use is associated with psychosis, aggression, paranoia, rapid physical deterioration, and significant social harms.
Cannabis (Dagga)
Cannabis (locally known as dagga) is the most widely used illicit substance in South Africa. While cannabis use was partially decriminalised for personal use in 2018, heavy or dependent use is associated with mental health problems — particularly psychosis and cannabis use disorder — especially when use begins in adolescence.
Heroin (Nyaope/Whoonga)
Nyaope (also known as whoonga) is a street drug mixture that typically contains heroin, combined with other substances. It is highly addictive and associated with severe withdrawal symptoms. Nyaope use is particularly prevalent in Gauteng and KwaZulu-Natal and is strongly associated with poverty, homelessness, and crime.
Prescription Medication Misuse
Misuse of prescription medications — including opioid analgesics, benzodiazepines, and stimulants — is a growing concern in South Africa, as it is globally. Prescription opioid misuse in particular has increased significantly in recent years.
Symptoms and Diagnostic Criteria
The DSM-5 diagnoses substance use disorder based on a pattern of use leading to clinically significant impairment or distress, manifested by two or more of the following within a 12-month period:
- Taking the substance in larger amounts or for longer than intended
- Persistent desire or unsuccessful efforts to cut down or control use
- Spending a great deal of time obtaining, using, or recovering from the substance
- Craving — a strong desire or urge to use the substance
- Failure to fulfil major obligations at work, school, or home
- Continued use despite persistent social or interpersonal problems caused by use
- Giving up or reducing important activities because of substance use
- Using in situations that are physically hazardous
- Continuing use despite knowing it is causing or worsening a physical or psychological problem
- Tolerance — needing more of the substance to achieve the same effect
- Withdrawal — characteristic symptoms when the substance is reduced or stopped
Severity is classified as mild (2–3 criteria), moderate (4–5 criteria), or severe (6 or more criteria).
Causes and Risk Factors
Neurobiological Factors
Psychoactive substances produce their effects by acting on the brain's reward system — primarily the mesolimbic dopamine pathway. Repeated substance use produces neuroadaptations that reduce the brain's natural reward responsiveness, increase sensitivity to substance-related cues, and impair inhibitory control. These changes help explain why addiction is characterised by compulsive use despite harmful consequences.
Genetic Factors
Genetic factors account for approximately 40–60% of the risk for substance use disorders. Having a first-degree relative with a substance use disorder substantially increases risk. Genetic factors influence both vulnerability to addiction and the subjective effects of substances.
Psychological Factors
Co-occurring mental health conditions — particularly depression, anxiety, PTSD, and ADHD — significantly increase the risk of substance use disorders. Substances may initially be used to self-medicate psychological distress, creating a cycle in which substance use worsens the underlying condition.
Social and Environmental Factors
Poverty, unemployment, trauma exposure, social disruption, peer influence, early initiation of substance use, and availability of substances all contribute to substance use disorder risk. In South Africa, the legacy of apartheid — including forced urbanisation, family separation, and community disruption — has created social conditions that increase vulnerability to substance misuse.
When to Seek Professional Help
Seek professional assessment if:
- You are using substances in ways that are causing harm to your health, relationships, or work
- You have tried to cut down or stop and found it difficult
- You are experiencing withdrawal symptoms when you reduce or stop use
- You are using substances to cope with emotional distress
- You are concerned about a family member's substance use
A GP is a good first point of contact. SADAG's substance abuse helpline is available at 0800 12 13 14. Under the National Health Act (Section 6), you have the right to be informed about your condition and to participate in decisions about your care.