Heroin: what are the effects?

The effects of heroin may last 3 to 5 hours.

Immediate effects

• Intense pleasure and a strong feeling of well-being.
• Confusion.
• Pain relief.
• Slowed breathing.
• Decreased blood pressure and heart rate.
• Constricted pupils.
• Dry mouth.
• Suppressed cough reflex.
• Reduced sexual urges.
• Drowsiness.
• Slurred and slow speech.
• Reduced co-ordination.
• Nausea and vomiting.

In greater quantities

The immediate effects intensify and last longer with higher quantities of heroin. The following effects are also likely to occur.

• The ability to concentrate is impaired.
• The user is likely to fall asleep (‘on the nod’).
• Breathing becomes shallower and slower.
• Nausea and vomiting are more likely to occur.
• Sweating, itching and increased urinary output are also likely.

Overdose

Using a large quantity of heroin can cause death. Breathing becomes very slow, body temperature drops, and the heartbeat becomes irregular.

Overdose may occur if:

• too much heroin is injected;
• the strength of purity is high; or
• heroin is used with alcohol or sedatives (benzodiazepines).

To reverse the effects of a heroin overdose, the attending ambulance officer will inject the drug naloxone to restart breathing. The naloxone may not last as long as the heroin, so the person will feel ‘stoned’ again and may even become unconscious again. It is important that another quantity of heroin is not taken again on that day, as it may combine with the original quantity of heroin taken and could cause an overdose.

After an overdose, it is strongly advisable to seek assessment at a hospital.

Short-term effects

Apart from overdosing, the major problem of short-term use of any opiate is the way it is used. For example, injecting heroin can result in skin, heart and lung infections, and diseases such as hepatitis and HIV.

Long-term effects

In its pure form, heroin is relatively non-toxic to the body, causing little damage to body tissue and other organs. However, there are some long-term effects, including dependence, constipation, menstrual irregularity and infertility in women, loss of sex drive in men, intense sadness and cognitive impairment.

Many of the other long-term problems may be the result of other factors, such as the person's poor general self-care, drug impurities and contaminants, and blood-borne viruses.

Heroin is usually a mixture of pure heroin and other substances, such as caffeine and sugar. Additives can be highly poisonous. They can cause collapsed veins, tetanus, abscesses and damage to the heart, lungs, liver and brain.

For more information, please click on the Australian Drug Foundation's DrugInfo Clearinghouse web site link below.

myDr, 2002. Reproduced with kind permission from the Australian Drug Foundation.
© Copyright: myDr, UBM Medica Australia, 2000-2010. All rights reserved.

Last Reviewed: 20 September 2006