Alcohol : ethanol and methanol

ethanol its sources, blood alcohol level , ethanol and methanol toxicity

1. Ethanol and Methanol Dr. Sumit Kumar

2. Introduction

3. Introduction… Alcoholic beverages: Malted liquors: Obtained by fermentation of germinating cereals e.g : Beers , Stout . Wines : Produced by fermentation of natural sugars present in grapes and other fruits. Light wines: A lcohol content 9–12%, never exceed 15% Fortified wines : Port , Sherry (16–22%) Effervescent wines: Champagne (12-16%): Bottled before fermentation is complete

4. Pharmacological properties

5. Metabolism:

6. Ratio of ethanol in end-expiratory alveolar air and blood is relatively constant B lood ethanol levels (BELs) in humans can be estimated readily by the measurement of alcohol levels in expired air Legally allowed BELs is below 80 mg% (80 mg /100 mL blood; 0.08% w/v)

7. INTERACTIONS

8. Effects Of Ethanol On Physiological Systems Local actions: Irritant and counter irritant Rubefacient Astringent and antiseptic Antiseptic of 20-70% , above 90% antisepsis decreases

9. Effects Of Ethanol On Physiological Systems……..

10. Neurohormonal mechanism of alcohol…

11. Alcohol enhance GABA release at GABAA sites in the brain. It also inhibits NMDA and kainate type of excitatory amino acid receptors ( operating through cation channels). Action of 5-HT on 5-HT3 inhibitory autoreceptor (having an intrinsic ion channel) is augmented. Release and turnover of DA in brain is enhanced through β endorphin release in nucleus accumbens and an opioid receptor dependent mechanism. Activity of membrane bound enzymes like Na+ K+ ATPase and adenylyl cyclase is also altered.

12. CVS Cardiac Arrhythmias: Abnormal cardiac conduction, Increase QT interval, Ventricular repolarization Atrial arrhythmias : Supraventricular tachycardia, atrial fibrillation, and atrial flutter Cardiomyopathy and strokes are also frequent Alcohol reduces risk of CHD I ncreases in high-density lipoprotein (HDL) E levates levels of tissue plasminogen activator tPA

13. GIT Esophageal reflux Barrett’s esophagus Traumatic rupture of the esophagus Mallory- weiss tears, and esophageal cance r Heavy alcohol disrupt the gastric mucosal barrier and cause acute and chronic gastritis. The primary effects are fatty infiltration of the liver, hepatitis, and cirrhosis. most common cause of both acute and chronic pancreatitis

14. Acute Ethanol Intoxication

15. Symptoms of acute acohol intoxication:

16. Treatment of acute alcohol intoxication

17. Tolerance, Dependence, And Chronic Ethanol Use

18. Treatment

19. Clinical use of Ethanol

20. foetal alcohol syndrome : Intrauterine and postnatal growth retardation Low IQ Microcephaly, Cranio -facial and other abnormalities, Susceptibility to infections. Increases incidence of miscarriage, Stillbirths Low Birth-weight babies

21. Methanol

22. M ethanol Methanol is a CNS depressant Toxic effects of methanol are largely due to formic acid A blood level > 50 mg/dl methanol is associated with severe poisoning 15 ml of methanol causes blindness fatal dose : 75–100 ml

23. Treatment of Methanol Poisoning Keep the patient in a quiet, dark room; protect the eyes from light Supportive measures to maintain ventilation and BP i.v . Sod. bicarbonate infusion to Combat acidosis Pot. chloride infusion to treat hypokalemia Ethanol (10% in water) is administered through a nasogastric tube, loading dose of 0.7 ml/kg is followed by 0.15 ml/kg/hour . Fomepizole a specific inhibitor of alcohol dehydrogenase and drug of choice for methanol poisoning loading dose of 15 mg/kg i.v. followed by 10 mg/kg every 12 hours till serum methanol falls below 20 mg/dl Folate therapy, leucovorin 50 mg injected 6 hourly

24. Thank you