Benzodiazepines act as agonists at the GABA-A receptor, enhancing the effect of the inhibitory neurotransmitter GABA. They have therapeutic effects for conditions like insomnia, anxiety, seizures, and muscle spasms by increasing the influx of chloride ions into neurons and hyperpolarizing the postsynaptic membrane. The document discusses the structure and subunits of the GABA-A receptor and how different benzodiazepines like lorazepam, midazolam, and diazepam have varying onset times, durations of action, and metabolism due to factors like receptor affinity, liposolubility, and pharmacokinetics. Adverse effects include respiratory and cardiovascular depression, especially when combined

1. BENZODIAZEPINAS
KAREM A. MARTINEZ F.
R1 ANESTESIOLOGIA Y REANIMACION
HSB

2. Aumentan actividad
Modulan actividad en la
Anillo heterociclico neurotransmisora
membrana pots sinaptica
inhibitoria
2 atomos de N estan Entrada de cloruro
Receptor GABA tipo A
localizados en 1-4 hiperpolarizacion
Desordenes de
suegno, ansiedad, estatus Acciones terapeuticas
epileptico y tension mediada
muscular
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493.
2011

5. Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-
493. 2011

6. • Heteropentamero
• Sitios de union para:
- Barbituricos
- Benzodiazepinas (Subunidad alpha y gamma 2)
- GABA
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011

7. Propiedades farmacologicas dependeran de la subunidad
(Histidina)
• Alpha 1-2-3-5 combinada con
• Betha 1-2-3 subunidades
• Gamma 2 (Brain-modulacion a BZN)
Insensibles a BZN
• Alpha 4-6
• Delta
• Aumentan o modulan afinidad por el neutotransmisor fisiologico GABA
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493.
2011

8. Cerebro y corteza
Evers, A, Maze M, Anesthetic
Pharmacology. Basic principles and clinical
practice. 2nd Edition. Chapter 29 Pag 483-

9. Miller s. anesthesia. 7thedition. Chapter 16.2011

10. • Los efectos tranquilizantes son asociados a bajas
dosis
• Lorazepam 2-3 veces mas sedante que Midazolam
• Midazolam 5-6 veces mas potente que Diazepam
• Lorazepam 4 veces mas amnesico que Midazolam
- Cuidado en pacientes ancianos
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493.
2011

11. Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493.
2011

12. • Lorazepam, midazolam y diazepam, los mas
utilizados en la practica clinica
• Difieren en inicio de accion, duracion y
terminacion de efectos
- Afinidad a los receptores y sus subunidades (potencia)
- Liposolubilidad (redistribucion)
- Farmacocinetica (Absorcion, distribucion, eliminacion)
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011

13. • 99% Diazepam Union a proteinas plasmaticas
• 95% Midazolam
• 85% Lorazepam
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011

14. MIDAZOLAM DIAZEPAM
HEPATICO
HEPATICO- HIDROXILACION OXIDATIVO N-
Enzimas microsomales DESMETILACION
Enzimas microsomales
HIDROXIMIDAZOLAM 20- DESMETILDIAZEPAM
30% OXAZEPAM
Es conjugado y eliminado Conjugacion glucuronizacion
renal Eliminacion renal
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493.
2011

15. Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011

16. EFECTOS ADVERSOS
• Depresion respiratoria
• Incremento con opioides
• Depresion cardiovascular
- Reversion con antagonista benzodiazepinas
FLUMAZENIL-1-2 minutos inicio de accion
- 45-90 minutos duracion de accion (0.2, 1.0 mg bolo o 3mg /H)
Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011

17. 1. Evers, A, Maze M, Anesthetic Pharmacology. Basic principles and
clinical practice. 2nd Edition. Chapter 29 Pag 483-493. 2011
BIBLIOGRAFIA