Heavy, consistent use of methamphetamines like ice can cause acute psychotic reactions in some but not all people. This is supported by data from several sources. For example, the 2017 Illicit Drug Reporting System (IDRS) found that thirty-two (3.6%) participants out of 888 injecting drug users reported a hospital admission for methamphetamine psychosis in the past year.
Some symptoms of methamphetamine psychosis include:
- Feeling suspicious (e.g. thinking you are being watched, picked on or that people are out to get you).
- Hallucinations (hearing, seeing or smelling things that don’t exist e.g. feeling like you have bugs under your skin, hearing someone calling your name when no-one is around or imagining things are changing shape or moving when they are not).
- Unusual thoughts (e.g. thinking other people are reading your mind or stealing your thoughts).
- Repetitive compulsive behaviour (e.g. cleaning, assembling/disassembling objects, washing your hands repeatedly).
- Muddled thoughts or incoherent speech.
These symptoms can last a few hours or up to a few days. A small number of people may find these symptoms last much longer (e.g. more than a few weeks), or continue even when a person is not using ice. This might mean that an underlying psychotic disorder, such as schizophrenia, is present.