What are the possible mechanisms involved in the occurrence of tolerance to chronic alcohol intake?

Tolerance to chronic alcohol intake causes the central nervous system to adjust to this chronic exposure. Adjustments include changes to the receptors and second messengers involved in the metabolism of alcohol. it also increases metabolism tempo.

The enzyme system MEOS (mixed function oxidases) is also partially responsible for tolerance. This enzyme system is involved when consuming higher concentrations of alcohol, 100mg/dL and above. 

What are the toxic effects of chronic alcohol consumption on the liver and hepatic metabolism?

Chronic alcohol consumption causes the following:

• Progressive decrease in liver function
• Hepatitis
• Liver cirrhosis
• Increased activity of liver microsomal enzymes
• Decreased gluconeogenesis
• Hypoglycaemia
• Fat accumulation (nutrient deficiencies contribute to this)

What is Wernicke-Korsakoff syndrome and how is it treated?

Wernicke-Korsakoff syndrome is peripheral neuropathy as a result of Thiamine (Vitamin B1) deficiency. This syndrome presents as: ataxia, confusion, paralysis of facial muscles, etc.

This can be treated by administering parenteral thiamine to prevent permanent damage.

Fully explain the Foetal Alcohol Syndrome.

The foetal alcohol syndrome is caused by consumption of alcohol during pregnancy. The alcohol causes teratogenic effects. If exposed to alcohol in uterus, it may exhibit development disabilities and cognitive and behavioural defects. This is because of damage to the developing neurons. It presents as: mental retardation, growth deficiency, microcephaly (smaller brain), characteristics under development of middle facial area.

How do the pharmacokinetic interactions of acute alcohol consumption differ from that of chronic alcohol consumption?

Acute alcohol consumption decreases the metabolism of drugs. This causes the drug to build up in the body and accumulative central nervous system suppression is a result. Drugs include: Phenothiazines, tricyclic anti-depressants and other sedative-hypnotics.

Chronic consumption of alcohol increases the metabolic transformation of other drugs. This causes a shortened effect of the drug.

Name 4 drug interactions th alcohol where the pharmacological effects of the other drugs are potentiated by alcohol.

• Vasodilators
• Hypoglycaemic drugs
• Aspirin
• Paracetamol

Sources 

Brand, L. 2021. Alcohols. Study unit 3 [PowerPoint Presentation]. Unpublished lecture notes on eFundi, FKLG312. Potchefstroom: NWU.