This lecture covers all the effects of alcohols on various systems of the body. It also covers the management of acute alcohol intoxication, withdrawal syndrome and alcohol dependence. Uses of Methanol as well pharmacology of its toxicity is also explained.

1. Dr. Sachin Gupta
2nd Year PG
Department of Pharmacology
UCMS

2. Ethanol
 Mechanism of Action
 PK
 Pharmacological Effects of Alcohol
 Treatment of Acute and Chronic Alcoholism
 Clinical Uses
Methanol

3. Enhances the action of GABA at GABAA receptor.
Inhibit the opening of Ca2+ channel linked to NMDA
receptor.

4. Absorption
 Rapidly from GIT
 Food delays absorption by delaying gastric emptying.
 Crosses BBB and Placental barrier.

5. Metabolism
 95% Metabolized
 5% excreted through breath, urine and sweat. (Breath Analyser
Test)
 Zero order kinetics – 8 to 12 ml per hour (drinking on empty
stomach- greater pharmacological effect)

7. What is Disulfiram like reaction ?
Drugs- Disulfiram, metronidazole, cifotetan and
cefoperazone, nitrofurantoin.
Effect- Nausea, vomiting, facial flushing, dizziness,
headache.

8. 1. Acute Intoxication
2. Chronic Alcoholism

9. CNS
1. Sedation, loss of inhibition, impaired judgement and driving
skills. (50-100 mg/dl)
2. Slurred speech, drunken gait. (120-160 mg/dl)
3. Vomiting and stupor (200-300 mg/dl)
4. Coma, respiratory and cardiac depression (>300 mg/dl)
Heart
1. Decreased myocardial contractility (~100mg/dl)
2. Fall in BP with large doses

10. Other Effects
1. Feeling of warmth because of cutaneous dilatation
2. Diuresis (-ADH)
3. Acute intake – hypoglycemia (NAD+ depletion inhibiting
gluconeogenesis)
4. Moderate amount – hyperglycemia (catecholamine release)
5. 7 Kcal/gram of nutritionally worthless food.

11. Effects on
a) Nervous System
b) Neurotoxicity
c) Liver and GIT
d) Cardiovascular System
e) Blood lipoproteins and Platelet Functions
f) Endocrine and Electrolyte Balance
g) Effect on Foetal development

12. Tolerance and Physical Dependence
 Normal function at high blood levels of 180 mg/dl (reduced
absorption and faster metabolism)
Withdrawal symptoms with physical dependence
 Hyper excitability, toxic psychosis and tremors
 After 8 hour of abstinence
Psychological dependence

13. Ataxia, dementia and peripheral neuropathies.
Wernicke- korsakoff syndrome (ataxia, confusion and
paralysis of extraocular muscles)
Impaired visual acuity

14. Fatty liver ->Hepatitis ->irreversible hepatic necrosis,
fibrosis and failure
Bleeding oesophageal Varices
Chronic pancreatitis
Induration of gut mucosa leading to nutritional
deficiencies.

15. Dilated cardiomyopathy
Hypertension

16. Increased HDL and Decreased LDL (moderate to normal
drinking of alcohol)
Megaloblastic anemia and iron deficiency anemia

17. Testicular atrophy, gynecomastia and impotence.

18. 6-10 units of alcohol per day
3 per 1000 live births born to such mothers
Microcephaly, mental retardation and flattened face.

19. Gastric lavage
Prevent aspiration of vomitus
I.V glucose
Thiamine i.v. (100 mg in 500 ml glucose infusion)or i.m.
Correction of electrolytes

20. Long acting sedative – hypnotics (chlor-diazepoxide or
diazepam)
Clonidine (inhibits exaggerated transmitter release)
Propranolol (inhibits excessive sympathetic effects)

21. 1. Aversion Therapy
 Make ethanol consumption unpleasant
 Disulfiram
 Rarely used now
2. Reduce the craving
a) Naltrexone (blunts the pleasurable high)
 50 mg once a day

22. b) Topiramate
 Potentiate inhibitory effect of GABA
c) Fluoxetine
 Increases serotonergic activity in CNS
d) Acamprosate
 Reduces the effect of glutamate on NMDA receptor
 Facilitate GABA transmission

23. Skin antiseptic (76% v/v)
Astringent action (to prevent bed sores)
Treatment of Methanol poisoning

24. It is added to industrial rectified spirit to render it unfit
for drinking.
Mixing of methylated spirit with alcoholic beverages by
bootlegers or its inadvertent ingestion results in methanol
poisoning.

26. Follows zero order kinetics
Toxic effects of methanol are largely due to formic acid,
since its further metabolism is slow and folate dependent.
A blood level of >50 mg/dl methanol is associated with
severe poisoning.
Even 15 ml of methanol has caused blindness and 30 ml
has caused death; fatal dose is regarded to be 75–100 ml.

27. 1. Inhibiting methanol metabolism to prevent toxic
metabolites
 Ethanol is preferred substrate for Alcohol dehydrogenase
 Ethanol (10% in water) is administered through a
nasogastric tube.
 Done along with Haemodialysis to remove unchanged
alcohol
 Fomepizole: competitive inhibitor of alcohol dehydrogenase

28. 2. Eliminating methanol and its toxic metabolites by dialysis
3. Combating Acidosis
 Sodium bicarbonate infusion
 To prevent retinal damage
4. Folate therapy
 Ca leucovorin 50 mg 6 hourly reduces blood formate levels.
5. Other measures
 Gastric lavage
 Support for respiration
 Protection of eyes from light