Skeletal muscle relaxants can be peripherally or centrally acting. Peripherally acting ones include neuromuscular blockers which can be depolarizing like succinylcholine or non-depolarizing like d-tubocurarine. They work by blocking neuromuscular transmission. Newer blockers have fewer side effects than older ones. They are used during surgery or mechanical ventilation. Centrally acting ones like dantrolene and baclofen work by reducing muscle tone. They are used for spasticity, spasms, and spastic neurological diseases.
this presentation gives the knowledge about the decongestants are a type of medication that can provide short relief for a blocked nose ................
short and simple study on the topic of laxative and purgatives which is very usefull for the student , teachers, as well as health cares peoples. this study is done by the student with the help of teachers
this presentation gives the knowledge about the decongestants are a type of medication that can provide short relief for a blocked nose ................
short and simple study on the topic of laxative and purgatives which is very usefull for the student , teachers, as well as health cares peoples. this study is done by the student with the help of teachers
This presentation was given by me during my M.pharm.
It contains description, classification, mechanism of actions and therapeutic uses of Neuromuscular blockers.
My all and slides mostly try to simplify pharmacy knowledge. Any time you are free to connect me. It's my pleasure to help you to get simplified pharmacy concepts. You may suggest topics needs to simplify the terminolog
Presentation on Antacids and antiulcer drugs. Introduction to ulcers, classification of antiulcer drugs, their pharmacological actions, uses and adverse effects.
Constipation is a comdition which causes difficulty in ecretion of feaces, less than three bowel in a week. the drugs that are used to treat constipation are cathartics.
Diarrhoea is a condition of excretion of loose stool and water equal or more than three bowel movement in a day. it is of three types, acute, dysentry, chronic diarrrhoea. may caused by bacteria E.coli, and Rotavirus in children. drugs used to treat are called anti diarrhoeal drugs.
local anaesthesia is defined as a loss of sensation in a circumscribed area of the body caused by a depression of excitation in nerve endings
Or an inhibition of the conduction process in peripheral nerves; no loss of consciousness occurs
Local anesthetics interfere with the excitation process in the nerve membrane in one or more of the following ways:
1) Altering the basic resting potential of the nerve membrane
2) Altering the threshold potential (firing level)
3) Decreasing the rate of depolarization*
4) Prolonging the rate of repolarization
This presentation was given by me during my M.pharm.
It contains description, classification, mechanism of actions and therapeutic uses of Neuromuscular blockers.
My all and slides mostly try to simplify pharmacy knowledge. Any time you are free to connect me. It's my pleasure to help you to get simplified pharmacy concepts. You may suggest topics needs to simplify the terminolog
Presentation on Antacids and antiulcer drugs. Introduction to ulcers, classification of antiulcer drugs, their pharmacological actions, uses and adverse effects.
Constipation is a comdition which causes difficulty in ecretion of feaces, less than three bowel in a week. the drugs that are used to treat constipation are cathartics.
Diarrhoea is a condition of excretion of loose stool and water equal or more than three bowel movement in a day. it is of three types, acute, dysentry, chronic diarrrhoea. may caused by bacteria E.coli, and Rotavirus in children. drugs used to treat are called anti diarrhoeal drugs.
local anaesthesia is defined as a loss of sensation in a circumscribed area of the body caused by a depression of excitation in nerve endings
Or an inhibition of the conduction process in peripheral nerves; no loss of consciousness occurs
Local anesthetics interfere with the excitation process in the nerve membrane in one or more of the following ways:
1) Altering the basic resting potential of the nerve membrane
2) Altering the threshold potential (firing level)
3) Decreasing the rate of depolarization*
4) Prolonging the rate of repolarization
skeletal muscle relaxants including dantrolene and diazepam.pptxDrSmithaRai
These are medicines which relax the skeletal muscles, used in surgical procedures as additional drugs to general anaesthetics, also used in sprains, muscle spasms, brief procedures like bronchoschopy laryngoscopy, endotracheal intubation, mechanical ventilation
Skeletal muscle relaxants are drugs that act peripherally at neuromuscular junction/ muscle fibre itself or centrally in the cerebrospinal axis to reduce muscle tone and/or cause paralysis. • A muscle relaxants is a drug that affects skeletal muscle function and decreases the muscle tone
This slide gives brief and complete description about depolarising and non depolarising skeletal muscle relaxants. The font size is also big and the number of words in each slide is also optimum so that it looks good when projected.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
7. Competitive neuromuscular blockers
(d-TC)
Mechanism of action
Muscle – flaccid paralysis, diaphragm affected last
Autonomic ganglia- d-TC: blocked-
Histamine release – d-TC, miva,
hypotension, bronchospasm
CVS- fall in BP
ganglionic blockade
histamine release
Decrease venous return (paralysis of muscle)
HR- increase : vagal ganglionic blockade
Atra, cisatra- hofmann elimination
Block is reversed by Anti-ChEase
8. Succinylcholine
Mechanism of action
Muscle – initial fasciculations followed by flaccid paralysis
Block is not reversed by Anti-ChEase
Metabolized by plasma Pseudocholinesterase- short acting (5-8 min)
ADR
•Muscle soreness,
•Hyperkalemia
•Increase IOP, ICP, IAP
•Cardiac arrhythmia
•Malignant hyperthermia
i.v dantrolene
•Prolonged apnea
Mechanical ventilation
FFP
9.
10. Advantages of newer neuromuscular
blockers over the older ones
• No or minimal ganglionic, cardiac or vascular
effects
• No or minimal histamine release
• Many a short acting: easy reversal
• Some are rapid acting: provide alternative to
SCh without the attendant complications.
11. Uses
1) As an adjuvant to General Anaesthesia
• During abdominal or thoracic surgery,
for endotracheal intubation
• To counteract laryngospasm during Barbiturate anaesthesia
• To prevent reflex muscle contraction during surgery
Selection of drug:
onset of action,
duration of blockade required,
on patient’s hepatic, renal and haemodynamic status.
•Example; SCh or Mivacurium : employed for brief procedure
(endotrachea intubation, laryngoscopy bronchoscopy)
12. • For longer duration suegery : Pipecurinium or
Doxacurium can be employed
• Renal or hepatic insufficiency: Atracurium or Cis-
atracurium (inactivated in plasma by Hoffmann
degradation)
2) To control Ventilation
• Ventilatory support - facilitated by continuous infusion
of subanaesthetic does of competitive neuromuscular
blocker which reduce the chest wall resistance to
inflation
13. 3) to prevent Trauma during electroconvulsive
therapy
• SCh with Diazepam: prevent injuries or fracture due to
excessive convulsion from ECT
• Mivacurium: alternative
4) Sever case of tetanus and status epilepticus
(not controlled Diazepam): paralysed by repeated dose
of a competitive blocker and maintained on intermittent
positive pressure respiration till disease subsides
15. Dantrolene
Mechanism of action
• RyR1 (Ryanodine Receptor) calcium channels
in the sarcoplasmic reticulum of skeletal
muscles and prevents Ca2+ induced Ca2+
release through these channels
• Dose:25–100 mg QID
16. Contd.
Uses
• reduces spasticity in upper motor neurone
disorders ,hemiplegia, paraplegia, cerebral palsy
• malignant hyperthermia:Used i.v
Adverse effects
• Muscular weakness
• Sedation, malaise, light headedness
• Diarrhoea
• Long term use:Liver toxicity
17. Use of centrally acting muscle relaxant
1) Acute muscles spasms
• Overstretching of a muscle, sprain, tearing of ligaments
and tendons, painful spasm of muscles , dislocation,
rheumatic disorders
• Mephenesin like and BZD muscle relaxants + analgesics :
commonly used
2) Torticolis, lumbago, backache, neuralgias
• Painful spasm of certain muscles : prominent feature
• Respond in the same way as acute muscle spasms.
18. • 3) Anxiety and tension
• Associated with ↑ tone of muscles.
• Diazepam group of drugs and chlormezanone benefit by
their antianxiety as well as muscle relaxant actions.
• 4) Spastic neurological diseases
• Impairment of descending pathways in the cerebrospinal
axis and withdrawal of inhibitory influence over the
stretch reflex
chronic ↑ in muscle tone or spasticity.
•Baclofen, Diazepam ,Tizanidine and Dantrolene
19. 5) tetanus
• Diazepam- infused i.v. and dose is titrated by the
response
• Methocarbamol : alternative
6) Electroconvulsive therapy
Diazepam↓ the intensity of convulsion resulting from ECT
• SCh: used in addition for total suppression of the
muscular component of ECT
7) Orthopedic manipulations
• Performed under the influence of diazepam or
methocarbamol given i.v.
Editor's Notes
The first drug that was found to be capable of blocking the skeletal neuromuscular junction was curare, which the native hunters of the Amazon in South America used to paralyze game. The drug tubocurarine [too-boe-kyoo-AR-een] was ultimately purified and introduced into clinical practice in the early 1940s. Although tubocurarine is considered to be the prototype agent in this class, it has been largely replaced by other agents due to side effects (see Figure 5.10). The neuromuscular blocking agents have significantly increased the safety of anesthesia, because less anesthetic is required to produce muscle relaxation, allowing patients to recover quickly and completely after surgery. Note: Higher doses of anesthesia may produce respiratory paralysis and cardiac depression, increasing recovery time after surgery.]
Mechanism of action
Nondepolarizing neuromuscular blocking drugs interact with the nicotinic receptors to prevent the binding of acetylcholine (Figure 5.8). These drugs thus prevent depolarization of the muscle cell membrane and inhibit muscular contraction. Because these agents compete with acetylcholine at the receptor without stimulating the receptor, they are called competitive blockers. Their action can be overcome by increasing the concentration of acetylcholine in the synaptic gap—for example, by administration of cholinesterase inhibitors, such as neostigmine, pyridostigmine, or edrophonium. Anesthesiologists often employ this strategy to shorten the duration of the neuromuscular blockade.
Actions: Not all muscles are equally sensitive to blockade by competitive blockers. Small, rapidly contracting muscles of the face and eye are most susceptible and are paralyzed first, followed by the fingers. Thereafter, the limbs, neck, and trunk muscles are paralyzed. Then the intercostal muscles are affected, and lastly, the diaphragm muscles are paralyzed. Those agents (for example, tubocurarine, mivacurium, and atracurium), which release histamine, can produce a fall in blood pressure, flushing, and bronchoconstriction.
Therapeutic uses: These blockers are used therapeutically as adjuvant drugs in anesthesia during surgery to relax skeletal muscle. These agents are also used to facilitate intubation as well as during orthopedic surgery.
Pharmacokinetics: All neuromuscular blocking agents are injected intravenously, because their uptake via oral absorption is minimal.
P.61
These agents possess two or more quaternary amines in their bulky ring structure, making them orally ineffective. They penetrate membranes very poorly and do not enter cells or cross the blood-brain barrier. Many of the drugs are not metabolized; their actions are terminated by redistribution (Figure 5.9). For example, tubocurarine, pancuronium, mivacurium, metocurine, and doxacurium are excreted in the urine unchanged. Atracurium is degraded spontaneously in the plasma and by ester hydrolysis. [Note: Atracurium has been replaced by its isomer, cisatracurium. Atracurium releases histamine and is metabolized to laudanosine, which can provoke seizures. Cisatracurium, which has the same pharmacokinetic properties as atracurium, is less likely to have these effects.] The aminosteroid drugs (vecuronium and rocuronium) are deacetylated in the liver, and their clearance may be prolonged in patients with hepatic disease. These drugs are also excreted unchanged in the bile. The choice of an agent will depend on how quickly muscle relaxation is needed and on the duration of the muscle relaxation. The onset and duration of action as well as other characteristics of the neuromuscular blocking drugs are shown in Figure 5.10.
Mechanism of action: The depolarizing neuromuscular blocking drug succinylcholine [suk-sin-ill-KOE-leen] attaches to the nicotinic receptor and acts like acetylcholine to depolarize the junction (Figure 5.11). Unlike acetylcholine, which is instantly destroyed by acetylcholinesterase, the depolarizing agent persists at high concentrations in the synaptic cleft, remaining attached to the receptor for a relatively longer time and providing a constant stimulation of the receptor. [Note: The duration of action of succinylcholine is dependent on diffusion from the motor end plate and hydrolysis by plasma cholinesterase.] The depolarizing agent first causes the opening of the sodium channel associated with the nicotinic receptors, which results in depolarization of the receptor (Phase I). This leads to a transient twitching of the muscle (fasciculations). Continued binding of the depolarizing agent renders the receptor incapable of transmitting further impulses. With time, continuous depolarization gives way to gradual repolarization as the sodium channel closes or is blocked. This causes a resistance to depolarization (Phase II) and a flaccid paralysis.
View Figure
Actions: The sequence of paralysis may be slightly different, but as with the competitive blockers, the respiratory muscles are paralyzed last. Succinylcholine initially produces short-lasting muscle fasciculations, followed within a few minutes by paralysis. The drug does not produce a ganglionic block except at high doses, but it does have weak histamine-releasing action. Normally, the duration of action of succinylcholine is extremely short, because this drug is rapidly broken down by plasma cholinesterase. However, succinylcholine that gets to the neuromusclular junction is not metabolized by acetylcholinesterase, allowing the agent to bind to nicotinic receptors, and redistribution to plasma is necessary for metabolism (therapeutic benefits last only for a few minutes). [Note: Genetic variants in which plasma cholinesterase levels are low or absent leads to prolonged neuromuscular paralysis.]
Therapeutic uses: Because of its rapid onset and short duration of action, succinylcholine is useful when rapid endotracheal intubation is required during the induction of anesthesia (a rapid action is essential if aspiration of gastric contents is to be avoided during intubation). It is also employed during electroconvulsive shock treatment.
Pharmacokinetics: Succinylcholine is injected intravenously. Its brief duration of action (several minutes) results from redistribution and rapid hydrolysis by plasma cholinesterase. It therefore is usually given by continuous infusion.
Adverse effects:
Hyperthermia: When halothane (see p. 133) is used as an anesthetic, administration of succinylcholine has occasionally caused malignant hyperthermia (with muscular rigidity and hyperpyrexia) in genetically susceptible people (see Figure 5.10). This is treated by rapidly cooling the patient and by administration of dantrolene, which blocks release of Ca2+ from the sarcoplasmic reticulum of muscle cells, thus reducing heat production and relaxing muscle tone.
Apnea: Administration of succinylcholine to a patient who is genetically deficient in plasma cholinesterase or has an atypical form of the enzyme can lead to prolonged apnea due to paralysis of the diaphragm.
Hyperkalemia: Succinylcholine increases potassium release from intracellular stores. This may be particularly dangerous in burn patients or patients with massive tissue damage in which postassium is been rapidly lost from within cells.
Decamethonium and SCh have affinity as well as submaximal intrinsic activity at the NM cholinoceptors. They depolarize
muscle end plates by opening Na+ channels (just as ACh does) and initially produce twitching and fasciculations. Because in the focally innervated mammalian muscle, stimulation is transient; longer lasting depolarization of muscle end plate produces repetitive excitation of the fibre. In the multiplely innervated contracture muscle (rectus abdominis of frog) stimulation is prolonged resulting in sustained contraction.
These drugs do not dissociate rapidly from the
receptor and are not hydrolysed by AChE. They
induce prolonged partial depolarization of the
region around muscle end plate → Na+ channels
get inactivated (because transmembrane potential
drops to about –50 mV) → ACh released from
motor nerve endings is unable to generate
propagated MAP → flaccid paralysis in
mammals. In other words a zone of inexcitability
is created around the end plate preventing
activation of the muscle fibre. In birds, the area
of depolarization is more extensive and spastic
paralysis occurs.