This document discusses antiepileptic drugs used to treat epilepsy. It begins by defining epilepsy as a chronic medical condition caused by sudden changes in brain electrical function, characterized by recurrent seizures. It then discusses the etiology, or causes, of epilepsy including congenital defects, injuries, infections, tumors and drug withdrawal. It provides details on commonly prescribed antiepileptic drugs like phenytoin, carbamazepine, valproate, phenobarbital and newer drugs. The treatment section covers guidelines for monotherapy versus polytherapy, monitoring drug levels, managing status epilepticus, and tapering off treatment.
Parasympatholytics are the drugs that block or inhibit the actions of acetylcholine at postganglionic nerve endings and cholinergic receptors. They are also referred to as anticholinergics or cholinergic blocking agents or antispasmodics.
Anticholinergic drugs include atropine and related drugs- atropine is the prototype. Atropine is obtained from the plant Atropa belladonna. Atropine and scopolamine (hyoscine) are the belladonna alkaloids. They compete with acetylcholine for muscarinic receptors and block this receptors-they are muscarinic antagonists.
ANTIEPILEPTIC DRUGS . mechanism of action of convulsionMsSapnaSapna
Anticonvulsants are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. A type of drug that is used to prevent or treat seizures or convulsions by controlling abnormal electrical activity in the brain.
Parasympatholytics are the drugs that block or inhibit the actions of acetylcholine at postganglionic nerve endings and cholinergic receptors. They are also referred to as anticholinergics or cholinergic blocking agents or antispasmodics.
Anticholinergic drugs include atropine and related drugs- atropine is the prototype. Atropine is obtained from the plant Atropa belladonna. Atropine and scopolamine (hyoscine) are the belladonna alkaloids. They compete with acetylcholine for muscarinic receptors and block this receptors-they are muscarinic antagonists.
ANTIEPILEPTIC DRUGS . mechanism of action of convulsionMsSapnaSapna
Anticonvulsants are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. A type of drug that is used to prevent or treat seizures or convulsions by controlling abnormal electrical activity in the brain.
anti epileptics drugs is a part of pharmacology. the topic contain information regarding epilepsy and their drug. ppt is short and simple and have correct information
1. Epilepsy, Seizure, Convulsion
2. Causes & Pathophysiology of Epilepsy
3. Classification and Choice of antiepileptics
4. Antiepileptics Mechanism of action of , Adverse effects, Drug interactions, General guidelines for use.
5. Recommendation to Antiepileptics and pregnancy according to RCOG 2016, SIGN 2017 guidelines
6. Treatment of status epilepticus according to American Epilepsy Society 2016 guidelines
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Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
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Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
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The Central Drugs Standard Control Organization (CDSCO) is India's national regulatory body for pharmaceuticals and medical devices. Operating under the Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, the CDSCO is responsible for approving new drugs, conducting clinical trials, setting standards for drugs, controlling the quality of imported drugs, and coordinating the activities of State Drug Control Organizations by providing expert advice.
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Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
2. Epilepsy
• It is a Chronic medical condition produced by
sudden changes in the electrical function of
the brain.
• It is a condition characterized by recurrent
episodes of seizures.
3. • Seizure- a paroxysmal abnormal discharge at
high frequency from neurons in cerebral
cortex.
• Convulsions- involuntary, violent, spasmodic
contractions of skeletal muscles.
4. Etiology
• Congenital defects, head injuries, trauma,
hypoxia
• Infection e.g. meningitis, brain abscess, viral
encephalitis
• Concussion, depressed skull, fractures
• Brain tumors (including tuberculoma), vascular
occlusion
• Drug withdrawal, e.g. CNS depressants
• Fever in children (febrile convulsion)
• Hypoglycemia, hypocalcemia
• Photo epilepsy
5. Drugs and Other Substances that
Can Cause Seizures
Drugs of abuse
• Amphetamine
• Cocaine
• Phencyclidine
• Methylphenidate
Anesthetics and analgesics
• Meperidine
• Tramadol
• Local anesthetics
Psychotropics
• Antidepressants
• Antipsychotics
• Li
Sedative-hypnotic drug
withdrawal
• Alcohol
• Barbiturates
• Benzodiazepines
8. A) Focal or partial
1) Simple partial( Jacksonian )- The electrical discharge is cofined to the
motor area.
2)Complex partial( psychomotor )- The electrical discharge is confined in
certain parts of the temporal lobe concerned with mood as well as
muscle.
B) Primary generalized
1) Tonic- clonic. Pt fall in convulsion & may bite his tongue & may lose control
of his bladder or bowel.
2) Tonic. Some pts, after dropping unconscious experience only the tonic phase
of seizure.
3) Atonic ( akinetic). Unconsciousness and relaxation of pt’s muscles & he
drops down.
4) Myoclonic . Sudden, brief shock like contraction which may involve the
entire body or be confined to the face, trunk or extremities.
5) Absence (petit mall) .momentary loss of consciousness without involving
motor area. Most common in children ( 4-12 yrs ).
EEG- symmetric 3 Hz spikes and wave pattern.
6) Status epilepticus ( re-occuring seizure ). Continuous seizure (>30 min)
without intervening return of consciousness.
9. • Lennox-Gastaut syndrome- occurs in children
and is defined by the following triad:
• (1) multiple seizure
• (2) EEG showing slow (<3 Hz) spike-and-wave
discharges
• (3) impaired cognitive function,associated
with CNS disease or dysfunction
10. Mesial temporal lobe epilepsy (MTLE)-
• characteristic hippocampal sclerosis
• refractory to treatment with anticonvulsants
but responds extremely well to surgical
intervention.
11.
12. PROLONGATION OF
N a+ CHANNEL
INACTIVATION
• Phenytoin
• Carbamazepine
• Valproate
• Lamotrigine
• Topiramate
• Zonisamide
INHIBITION OF 'T' TYPE Ca2+
CURRENT
• Ethosuximide
• Trimethadione
• Valproate
FACILITATION OF
GABA MEDIATED
Cl CHANNEL OPENING
• Barbiturate (Barb.)
• Benzodiazepine (Bzd.)
• Vigabatrin (Viga.)
• Valproate (Valpr.)
• Gabapentin (Gabp.)
• Tiagabine (Tiag.)
13.
14.
15.
16.
17.
18. TREATMENT OF SEIZURES
Drugs
Seizure disorder
Valproate
Topiramte
Lamotrigine
Tonic-clonic(Grand mal)
Drug of Choice
Carbamazepine
Phenobarbital
Phenytoin
Alternatives:
Carbamazepine
Phenytoin
Valproate
Partial (simple or complex)
Drug of choice
Phenobarbital
Lamotringine (as adjunct or alone)
Gabapentin (as adjunct )
Alternatives:
19. Treatament cont,d
Valproate
Ethosuximide
Absence ( petit mal)
Drug of choice
Clonazepam, Lamotrigine
Alternatives:
Valproate
Myoclonic, Atonic
Drug of choice
Clonazepam
Alternatives:
Lorazepam, Diazepam, i.v.
or Phenytoin, i.v. or Vaproate
Status Epilepticus
Drug of choice
Phenobarbital, i.v
Alternatives:
Diazepam, rectal*
Diazepam ,i.v
Valproate
Febrile Seizures
20. Treatment:
• Up to 80% of pts can expect partial or complete
control of seizures with appropriate treatment.
• Antiepileptic drugs suppress but do not cure
seizures
• Antiepileptics are indicated when there is two or
more seizures occurred in short interval (6m -1 y)
• An initial therapeutic aim is to use only one drug
(monotherapy)
21. Treatment ( Cont. )
• Advantage of monotherapy:
• fewer side effects, decreased drug-drug interactions, better
compliance, lower costs
• Addition of a second drug is likely to result in significant
improvement in only approx. 10 % of patients.
22. Treatment ( Cont. )
• when a total daily dose is increased, sufficient time
(about 5 t 1l2) should be allowed for the serum
drug level to reach a new steady-state level.
• The drugs are usually administered orally
• The monitoring of plasma drug levels is very
useful
• Precipitating or aggravating factors can affect
seizure control by drugs
23. Treatment ( Cont. )
• The sudden withdrawal of drugs should be avoided
withdrawal may be considered after seizure- free
period of 2-3 or more years
• Relapse rate when antiepileptics are withdrawn is 20 -
40 %
25. When to Withdraw Antiepileptic Drugs?
Normal neurological examination
Normal IQ
Normal EEG prior to withdrawal
Seizure- free for at least 3 yrs
NO juvenile myoclonic epilepsy
27. Phenytoin
Pharmacokinetics
• Well absorbed when given orally, however, it is also available as iv. (for emergency)
• 80-90% protein bound
• Induces liver enzymes (Very Important)
• Metabolized by the liver to inactive metabolite
• Metabolism shows saturation kinetics and hence t ½ increases as the dose increased
• Excreted in urine as glucuronide conjugate
• Plasma t ½ approx. 20 hours
• Therapeutic plasma concentration 10-20 µg/ml (narrow)
• Dose 200-400 mg/day
28. Phenytoin ( Cont. )
Mechanism of Action:
Membrane stabilization by blocking Na & Ca influx
into the neuronal axon.
or inhibits the release of excitatory amino acids via
inhibition of Ca influx
Clinical Uses:
Used for partial Seizures & generalized tonic-clonic
seizures. But not effective for absence Seizures .
Also can be used for Rx of ventricular fibrillation.
29. Side effects:
Dose Related:
• G.I.T upset
• Neurological like headache, vertigo,
ataxia, diplopia, nystagmus
• Sedation
• Intimal damage & thrombosis of vein-
So rate of injection s/b < 50mg/min
30. Side effects of Phenytoin ( Cont. )
Non-dose related:
• Hyperplasia of Gingival
• Hirsutism
• Hypersensitivity reactions (mainly skin rashes and lesions,
mouth ulcer)
• Hepatitis –rare
• Hydantoin syndrome- Fetal malformations- esp. cleft plate,
hypoplastic phalanges, microcephaly)
• Bleeding disorders (infants)
• Osteomalacia due to abnormalities in vit D metabolism
• Megaloblastic anaemia
31. • Side effects of phenytoin ( Cont.)
• Pharmacokinetic Interactions
– Inhibitors of liver enzymes elevate its plasma levels
e.g. Chloramphenicol, INH,etc.
– Inducers of liver enzymes reduce its plasma levels
e.g. Carbamazipine; Rifampicin.
32. CARBAMAZEPINE
Its mechanism of action and clinical uses are similar to that
of phenytoin. However, it is also commonly used for Rx of
mania and trigeminal neuralgia.
Pharmacokinetics
available as an oral form only
Well absorbed
80 % protein bound
Strong inducing agent including its own (can lead to failure of
other drugs e.g. oral contraceptives, warfarin, etc.
Metabolized by the liver
33. Pharmacokinetics of CBZ( Cont. )
• Excreted in urine as glucuronide conjugate
• Plasma t1/2 approx. 30 hours
• Therapeutic plasma concentration 6-12 µg/ml
(narrow).
• Dose 200-800 mg/day (given BID as sustained
release form)
34. • Side Effects of Carbamazepine:
• G.I upset
• Drowziness, ataxia and headache; diplopia
• Hepatotoxicity- rare
• Congenital malformation (craniofacial anomalies &
neural tube defects).
• Hyponatraemia & water intoxication.
• Late hypersensitivity reaction (erythematous skin rashes,
mouth ulceration and lymphadenopathy.
• Blood dyscrasias as fetal aplastic anemia (stop
medication); mild leukopenia (decrease the dose)
35. Pharmacokinetic interactions of CBZ
• Inducers of liver enzymes reduce its
plasma level
e.g. Phenytoin; Phenobarbital; Rifampicin
• inhibitors of liver enzymes elevate its
plasma levels
e.g. erythromycin,INH ,verapamil;
Cimetidine
37. Sodium Valproate or Valproic Acid
• Pharmacokinetics :
• Available as capsule, Syrup, I.V
• Metabolized by the liver ( inactive )
• High oral bioavailability
• Inhibits metabolism of several drugs such as
Carbamazepine; phenytoin, Topiramate and
phenobarbital.
• Excreted in urine ( glucuronide )
• Plasma t1/2 approx. 15 hrs
38. Sodium valproate ( cont. )
Mode of action (by all possible methods)
• Increase in GABA content of the brain (inhibits GABA –
transaminase and succinic semialdehyde dehydrogenase)
39. Sodium Valpraote ( cont. )
• Clinical Use:
–Very effective against absence, myoclonic
seizures.
–Also, effective in gen. tonic-clonic siezures
(primarly Gen)
–Less effective as compared to carbamazepine for
partial seizures
–Like Carbamazepine also can be used for Rx of
mania
40. • Side Effects of Sod. valproate:
• Nausea, vomiting and GIT disturbances (Start
with low doses)
• Increased appetite & weight gain
• Transient hair loss.
• Hepatotoxicity
• Thrombocytopenia
• Neural Tube defect (e.g. Spina bifida) in the
offspring of women. (contraindicated in
pregnancy)
41. Newer Antiepileptic Drugs
( Second- Generation )
1. Vigabatrin 1989
2. Gabapentin 1993**
3. Lamotrigine 1994**
4. Topiramate 1996**
5. Tiagabine 1997
6. levetiracetam 1999
7. Oxcarbazepine 2000 (safety profile similar to CBZ).
Hyponatremia is also problem, however it is less likely
to cause rash than CBZ.
8. Zonisamide 2000
42. • NEWER AGENTS DIFFER FROM OLDER
DRUGS BY
Relatively lack of drug-drug interaction
(simple pharmacokinetic profile) Improved
tolerability
HOWEVER THEY ARE
Costly with limited clinical experience
43. Lamotrigine
Pharmacological effects
Resembles phenytoin in its pharmacological effects
Well absorbed from GIT
Metabolised primarily by glucuronidation
Does not induce or inhibit C. P-450 isozymes ( its metabolism is
inhibitted by valproate )
Plasma t 1/2 approx. 24 hrs.
• Mechanism of Action:
Inhibits excitatory amino acid release (glutamate & aspartate )
by blockade of Na channels.
• Uses: As add-on therapy or as monotherapy
• Side effects:
• Skin rash, somnolence, blurred vision, diplopia, ataxia,
headache, aggression, influenza – like syndrome
44. Gabapentin
• Structural analogue of GABA .May increase the
activity of GABA or inhibits its re-uptake.
Pharmacokinetics:
Not bound to proteins
Not metabolized and excreted unchanged in urine
• Does not induce or inhibit hepatic enzymes (similar
to lamotrigine)
• Plasma t ½ 5-7 hours
45. Gabapentin ( Cont. )
• Side effects:
• Somnolence, dizziness, ataxia, fatigue and
nystagmus.
• Uses:
• As an adjunct with other antiepileptics
• Pain due to diabetic neuropathy, postherpetic
neuralgia
46. Topiramate
• Pharmacological Effects:
• Well absorbed orally ( 80 % )
• Food has no effect on absorption
• Has no effect on microsomal enzymes
• 9-17 % protein bound ( minimal )
• Mostly excreted unchanged in urine
• Plasma t1l2 18-24 hrs
• Mechanism of Action:
• Blocks sodium channels (membrane stabilization)
and also potentiates the inhibitory effect of GABA.
47. Topiramate (cont’d)
Side effects:
• Psychological or cognitive dysfunction
• Weight loss
• Sedation
• Dizziness
• Fatigue
• Urolithiasis
• Paresthesias (abnormal sensation )
• Teratogenecity (in animal but not in human)
48. Vigabatrin (restricted)
Pharmacological effects:Drug of choice for infantile
spasms
• Not bound to proteins ,Not metabolized and
excreted unchanged in urine
• Plasma t1/2 4-7 hrs
Mechanism of action :
Inhibits GABA metabolising enzyme & increase GABA
content in the brain( similar to valproate).
Side effects:
Visual field defects, psychosis and depression (limits
its use).
49. Zonisamide
Pharmacokinetics:
• Well absorbed from GIT (100 %)
• Protein binding 40%
• Extensively metabolized in the liver
• No effect on liver enzymes
• Plasma t ½ 50 -68 hrs
Mech of action: Prolongation of sodium channel inactivation
Clinical Uses:
Add-on therapy for partial seizures
Side Effects:
Drowsiness, ataxia , headache, loss of appetite, nausea &
vomiting, Somnolence .
50. Tiagabine
• Adjunctive therapy in partial and generalized tonic-clonic seizures
• Pharmacological effects
• Bioavailability > 90 %
• Highly protein bound ( 96% )
• Metabolized in the liver
• Plasma t ½ 4 -7 hrs
• Mode of action:
• inhibits GABA uptake and increases its level
52. Clinical Advices for the Use of Drugs in the
Treatment of Epilepsy.
• General features:
• It is essential to have an accurate and
comprehensive diagnosis.
• Must treat underlying causes e.g. hypoglycemia ,
infection and tumor
• Diagnosis: Adequate description of symptoms both
from patient and eye witness.
• EEG( supportive)
53. Clinical Advices ( Cont. )
• EEG should not be an indication for confirming
epilepsy nor to stop treatment for seizure free
patients.
• 20% of pts admitted after positive recording with
EEG did not have the disorder (Betts,1983 )
54. Common Causes of Failure of
Antiepileptics
1. Improper diagnosis of the type of seizures
2. Incorrrect choice of drug
3. Inadequate or excessive dosage
4. Poor compliance
55. Antiepeliptics and Pregnany:
– Seizure very harmful for pregnant women.
– Monotherapy usually better than drugs
combination.
– Folic acid is recommended to be given for every
pregnant women with epilepsy
– Phenytoin, sodium valproate are absolutely
contraindicated and oxcarbamazepine is better
than carbamazepine.
– Experience with new anticonvulsants still not
reliable to say that are better than old ones.
56. MCQs
Q 1.Which one of the following antiepileptic
drugs does NOT act by Na+channel
modulation?
A. Phenytoin
B. Carbamazepine
C. Lamotrigine
D. Phenobarbitone
• Ans D
57. Q2. Which one of the following antiepileptic
drugs can cause permanent vision loss?
A. Lacosamide
B. Vigabatrin
C. Topiramate
D. Levetiracetam
• Ans - B
58. Q3. Mechanism of action of vigabatrin is
A. Increase in GABA concentration
B. Sodium channel blockade
C. NMDA receptor blockade
D. Calcium channel blockade
• Ans- A
59. Q4. Mechanism of action of ethosuximide is
A. Reduction of low threshold Ca2+ current (T-
type current)
B. Sodium channel blockade
C. Increase in GABA
D. NMDA receptor blockade
• Ans- A
60. Q5. Ethosuximide is the drug of choice in:
A. Absence seizures
B. Febrile convulsions
C. Generalized tonic clonic seizures
D. Myoclonic seizures
Ans- A
61. Q6. Which one of the following is broad-
spectrum anti-seizure drug?
A. Ethosuximide
B. Valproate
C. Phenytoin
D. Phenobarbital
• Ans-B
63. Bibliography
Bibliography
• Essentials of Medical Pharmacology -7th edition by KD Tripathi
• Goodman & Gilman's the Pharmacological Basis of Therapeutics 12th
edition by Laurence Brunton (Editor)
• Lippincott's Illustrated Reviews: Pharmacology - 6th edition by Richard A.
Harvey
• Basic and Clinical pharmacology 11th edition by Bertram G Katzung
• Rang & Dale's Pharmacology -7th edition
by Humphrey P. Rang
• Clinical Pharmacology 11th edition By Bennett and Brown, Churchill
Livingstone
• Principles of Pharmacology 2nd edition by HL Sharma and KK Sharma
• Review of Pharmacology by Gobind Sparsh