Symptoms of alcohol withdrawal vary from mild to severe, depending on the duration and quantity of alcohol consumption. Within 6 hours of cessation, mild symptoms such as anxiety, shaky hands, headache, nausea, vomiting, insomnia and sweating may occur. Between 12 to 48 hours after the last drink, more severe symptoms can manifest, including hallucinations and seizures. From 48 to 72 hours post-cessation, a small percentage of individuals (about 5%) may experience delirium tremens (DTs), characterised by vivid hallucinations, delusions, confusion, a rapid heart rate, high blood pressure, fever and heavy sweating.

This category includes benzodiazepines, barbiturates, GHB and γ-butyrolactone (GBL) with withdrawal symptoms that mirror those of alcohol due to similar physiological impacts. The timing of symptom onset varies by substance offering clues to the specific cause. For example, GHB withdrawal symptoms emerge rapidly post-cessation, contrasting with the delayed onset associated with benzodiazepines due to their active metabolites.

Opioid withdrawal symptoms are the adverse effects experienced when stopping or reducing opioid medicines or when a medication blocking opioids is taken. These symptoms include physical discomforts such as hot and cold flushes, sweating, goosebumps, anxiety, irritability, cravings, gastrointestinal issues like nausea and diarrhea, tremors, watery eyes, runny nose, sneezing, yawning and sleep disturbances. Pain in various forms, such as joint, bone, muscle, abdominal and headaches, can also occur. It’s important to taper off opioids gradually under medical supervision to manage these symptoms effectively.

Antidepressant discontinuation syndrome symptoms usually start within 2-4 days after stopping an antidepressant. They can include flu-like symptoms (fatigue, headache, achiness, sweating), vivid dreams or nightmares, nausea (sometimes vomiting), dizziness, light-headedness, burning or tingling sensations (paresthesia) and mood changes (anxiety, irritability, agitation, aggression). While symptoms are generally mild, a study showed that 7% of affected individuals experienced symptoms for two months, 6% for a year and 2% had symptoms beyond three years. It’s advised to consult a healthcare provider if experiencing these symptoms.

Neonates exposed to addictive substances in utero may experience withdrawal with symptom onset and presentation varying by substance. Alcohol withdrawal in neonates, distinct from fetal alcohol syndrome, can present with agitation, tremors and cardiovascular symptoms. Neonatal withdrawal from opioids and other substances may include a range of symptoms from jitteriness to seizures.