Showing posts with label Toxicology. Show all posts
Showing posts with label Toxicology. Show all posts

Monday, December 10, 2018

Atropine poisoning

Atropine poisoning is also called as Anti-muscarinic poisoning.

It is caused due to ingestion of :-
1) Datura plant
2) ‎Atropa belladona
3) Hyoscyamus
4) ‎Anti-histamine drugs
5) Anti-psychotic drugs
6) ‎Anti-depressants like TCA
7) ‎Anti-Parkinsonism

Clinical features:

Let's go from head to toe!

1) Brain:
Atropine causes following symptoms
-Hallucinations
-‎Confusion
-‎Delirium

Also called as Mad as hatters!

Remember: Atropine drives you crazy!

2) Eyes:
AcH causes constriction of pupils. No or less AcH causes Mydriasis

Fun fact 1: In ancient times, women used to apply Atropa belladona in eye for attracting men by dilating pupil.

Fun fact 2: Most of the dinner dates are candle night dinner, why? To dilate pupils and look attractive.
Also described as "Blind as a bat"

Remember: Atropine makes you look seductive!

3) Eyes and Mouth:-
AcH is responsible for secretion of saliva and tears.
Lack of AcH action causes - Dry mouth and Dry eyes.

Also described as "Dry as a bone"
Most common feature in Adults.

Remember: Atropine Dries you!

4) Face:
AcH causes constriction of blood vessels. Atropine blocks this action and hence causes dilation of the blood vessel. Hence this causes flushing of face.

Also described as - Red as a beet.

Remember: Atropine makes you blush!

5) Body temperature:
AcH is responsible for secretion of the glands. Lack of secretion causes decrease or no cooling effect. Hence it causes-Hyperthermia.

Also described as - Hot as a hare
Most common feature in children.

Remember: Atropine makes you hot!

Most common cause of death is Respiratory paralysis.
Next common is Shock.

I remember all this feature with the help of story:

I went on a candle night dinner with hot girl. Ofcourse, she was blushing because I'm crazy to have dry resins after dinner! (Okay that's lame and I know!)

Key points:-

Candle night dinner - Mydriasis
Hot-Hyperthermia
Blushing-Flushing of face
Crazy-Deliruim, Hallucination and confusion
Dry resins-Dry secretion

Treatment:
1) Supportive treatment:

Gastric lavage using Tannic acid : To remove unabsorbed poison. Avoid potassium permagnate.

Forced acidic diuresis: Because Atropine is an alkaline drug

Seizures are treated by Diazepam

Patient is kept in dark quiet room-To avoid hallucination.

Ice bags given to treat maintain temperature.

2) Antidote: Physostigmine since it crosses BBB.

That's it
-Demotional bloke.

Thursday, November 1, 2018

Algorithmic Management of Organophosphate Poisoning

Hey guys, this whiteboard provides a general overview of how to manage patients with OrganoPhosphorous Compounds (OPC) poisoning.

      [Please click on the image to enhance it]

*Use of benzodiazepines has been associated with decreased mortality and morbidity, even in the absence of convulsions.

Signs of atropinization refer to the target end-points for atropine therapy and includes:
- Clear chest on auscultation, no wheeze
- Heart rate >80 beats/min
- Systolic Blood Pressure >90 mmHg
- Dry axillae
- Pupils no longer pin-point (miotic)

Early treatment with oximes is necessary before phosphorylated cholinesterase enzymes undergo “aging” and become resistant to reactivation (due to loss of their alkyl group).

That would be all.
Happy studying!

- Ashish Singh.

Thursday, July 27, 2017

Image based question on toxicology

Hello awesomites!

Yesterday, we posted an Image based MCQ - And as promised, here is the answer!

#FMT
#Pharmacology 

Q. A child accidentally consumed a fruit shown in the picture. Which of the following drugs is used for management?


A. Neostigmine
B. Pyridostigmine
C. Physostigmine
D. Atropine

The correct answer is C. Physostigmine.
The plant shown in the picture is Datura Stramonium. It contains Atropine which is Anticholinergic. The drug of choice for Anticholinergic toxicity is Physostigmine.

MD Mobarak Hussain (Maahii)

Monday, June 19, 2017

Baclofen for treatment of alcohol dependence

Hello!

Recent evidence suggest that the gamma-aminobutyric acid-B receptor agonist baclofen is a promising agent for the treatment of alcoholism.

Yep!

Baclofen produces an effortless decrease or suppression of alcohol craving. It decreases alcohol consumption including in those with poor motivation. The drug causes few side effects and does not add to the intoxication effect of alcohol.

It benefits patients with alcohol dependence (even those who are still in precontemplation stage of motivation!)

Research has shown that baclofen reduces withdrawal symptoms of alcohol and is safe in those with liver impairment.

Although further studies that compare long-term alcohol-related outcome of baclofen with established drugs such as naltrexone and disulfiram are needed.

Interesting, isn't it?

-IkaN

Wednesday, May 24, 2017

NBME 7 question on intoxication

Disclaimer: This is an NBME form 7 question for step 2 CK. If you are planning to take USMLE step 2 CK in the future, I would recommend that you DO NOT read this post because it will bias your assessments.

Monday, May 22, 2017

Fact of the day: Marchiafava-Bignami disease

Marchiafava-Bignami disease is a rare disorder of demyelination or necrosis of the corpus callosum and adjacent subcortical white matter that occurs predominantly in malnourished alcoholics. Dementia, spasticity, dysarthria, and inability to walk may present as an acute, subacute or chronic condition.

Lesions appear as hypodense areas in portions of the corpus callosum on CT and as discrete or confluent areas of decreased T1 signal and increased T2 signal on MRI. Alcohol abusers without liver disease, amnesia, or cognitive dysfunction show thinning of the corpus callosum at autopsy and on MRI, suggesting that alcohol or malnutrition damages the corpus callosum commonly in the absence of the necrotic lesions of Marchiafava-Bignami disease.

Interesting, isn't it?
-IkaN

Friday, May 19, 2017

No cyanosis in cyanide poisoning. Why?

I was reading about cyanide poisoning today and saw "Cherry red skin" in the clinical manifestations. I know that carbon monoxide poisoning causes a cherry red color to blood. But why cyanide?

The curiosity lead to this post.

In normal cellular metabolism, most adenosine triphosphate (ATP) is generated from oxidative phosphorylation. .

Cyanide avidly binds to the ferric ion (Fe3+) of cytochrome oxidase a3, inhibiting this final enzyme in the mitochondrial cytochrome complex. When this enzyme's activity is blocked, oxidative phosphorylation ceases. The cell must then switch to anaerobic metabolism of glucose to generate ATP.

Anaerobic metabolism leads to the formation of lactic acid and the development of metabolic acidosis. Hydrogen ions produced by ATP hydrolysis are no longer consumed in aerobic ATP production, exacerbating this acidosis. Serum bicarbonate decreases as it buffers excess acid, leading to an increased anion gap.

Despite an ample oxygen supply, cells cannot utilize oxygen because of their poisoned electron transport chain. This functional (or "histotoxic”) hypoxia is particularly deleterious to the cardiovascular and central nervous systems (especially the basal ganglia).

Because of the decreased utilization of oxygen by tissues, the venous oxyhemoglobin concentration will be high, making venous blood appear bright red.

Therefore, despite hypotension, apnea, and/or bradycardia, the patient does not usually appear cyanotic in the setting of cyanide poisoning.

Clinical features:
Central nervous system toxicity is the most prominent in cyanide toxicity – Headache, anxiety, confusion, vertigo, coma, seizures.

Which should you suspect cyanide poisoning?
Victims of fires
Reported ingestions
Treatment with sodium nitroprusside

Antidote:
Hydroxocobalamin
Sodium thiosulfate
Nitrites (to induce methemoglobinemia)

That's all!
-IkaN

Thursday, May 18, 2017

Theophylline toxicity mnemonic

Theophylline's effects arise from antagonism of adenosine receptors and indirect adrenergic activity.
It is used as a bronchodilator for patients with asthma or chronic obstructive pulmonary disease.

Sunday, April 30, 2017

Phencyclidine intoxication mnemonic

A combative, agitated, psychotic patient with multi directional nystagmus, tachycardia and hypertension. 

Yup. You guessed it right. It's PCP intoxication. 

Here's a mnemonic 

Sunday, June 22, 2014

Antidotes and chelating agents mnemonic

Hey everyone! Long time, is it not?

We'll be learning about chelating agents today!

The antidote for copper poisoning is pencillamine.
How do I remember that?
"Copper pennies"
Penicillamine - Copper poisoning.

Dimercaprol is also known as British Anti Lewisite.
"BAL GAL" (It rhymes lol) or "British gal" is my mnemonic for remembering for which toxins' treatment it is used!
British Anti Lewisite - Gold, Arsenic, Lead.

Sometimes you find the answer in the word itself!
diMERcaprol - MERcury posioning.