Pain Drugs Flashcards
List the Non-Opioid Analgesics
- Aspirin
- Acetaminophen
- NSAIDs
- Cox-2 Inhibitors
What is the MOA of Non-Opioid Analgesics?
Target inflammatory components of the pain cascade
What is the use of Non-Opioid Analgesics?
Mild to Moderate Pain
-Ex: soft tissue injury, sprain, strain, HA, arthritis
Non-Opioid Analgesics may be beneficial when used synergistically with what types of drugs?
Opioids
What is a major side effect of Acetaminophen?
Hepatotoxicity/Liver Failure
What is a major side effect of Aspirin and NSAIDs
- Gastric Ulcers
2. Inhibition of Platelet aggregation
What is a contraindication of Acetaminophen?
Alcoholics or Liver Disease Pts
What is a contraindication of NSAIDs
Use in patients who are taking Aspirin for CV protection
What are Opioid Receptors?
The opioid receptors are G Protein Coupled Receptors lined to Gi/o. There are 3 types: Mu, Delta and Kappa
What happens upon binding of an Opioid Receptor?
Activation results in inward rectifying K channels, inhibition of Ca channels, and inhibition of Adenylyl Cyclase
Where are Mu receptors found?
- CNS (neocortex, Thalamus, Hippocampus/Amygdala, Nucleus Acumbens)
- Myenteric Neurons of the Gut
- Vas Deferens
What are the physiological effects of Mu Receptor Activation?
- Supraspinal analgesia
- Respiratory Depression
- Euphoria/Dependence
- Constriction of the Gastric Tract
Where are Delta Receptors found?
- Olfactory Bulb
- Nucleus Acumbens
- Caudate and Putamen
- Neocortex
What is the physiological effect of Delta Receptor activation?
- Affects Behavior
Where are Kappa receptors found?
- Cortex
- Nucleus Acumbens
- Spinal Cord
What is the physiological effect of Kappa Receptor activation?
- Spinal Cord Analgesia
2. Sedation
What are the endogenous agonists of Mu receptors?
- Endomorphin 1 and 2
- Enkephalins
- B-endorphin
What are the endogenous agonists of Delta receptors?
- Enkphalins
What are the endogenous agonists of Kappa receptors?
- Dynorphins
Which drugs are Mu receptor agonists?
- Morphine
- Fentanyl
- Methadone
- Meperidine
- Buprenorphine
Which drugs are Mu Antagonists?
- Naloxone
2. Naltrexone
Which drugs are Delta Antagonists?
- Naltrindole
Which drugs are Kappa Agonists?
- Butorphanol
- Pentazocine
- Nalbuphrine
What are the strong Opioid Agonists?
- Morphine
- Hydromorphone
- Hydrocodone
- Methadone
- Heroin
- Oxycodone
- Meperidine
- Fentanyl + Analogs
Which drug is used for moderate-severe acute and chronic pain and for treatment of pain from PE and MI?
Morphine
Which drug is good for chronic pain and antitussive effects?
Hydrocodone
Which drug is good for severe pain? This drug is also a ketone of Morphine, is 7x stronger and has fewer active metabolites.
Hydromorphone
Which drug causes analgesia and is good for controlled withdrawal from opioid due to its long T1/2 and slow tolerance rate?
Methadone
Oxycodone is used for what?
Moderate-Severe pain
Which drug is used for acute analgesia, especially for OB?
Meperidine
Which drug is goof for surgery and post-surgery analgesia, and chronic pain for cancer patients (usually as a patch since the duration is short)?
Fentanyl + analogs
Which drugs are moderate-low agonists?
- Codeine
2. Propoxyphene
Which drug is used as an analgesic + antitussive?
Codeine
Which drugs are mixed agonists/antagonists (partial agonists)?
- Buprenorphine
- Pentazocine
- Butorphanol
- Nalbuphine
Which drug is a partial agonist at Mu Receptors?
Buprenorphine
Pentazocine, Butorphanol and Nalbuphine are partial agonists at what receptor?
Kappa
What drug is used for opioid withdrawal, detoxification and maintenance?
Buprenorphine
What are the Opioid Antagonists?
- Naloxone
- Naltrexone
- Nalmefene
Which drug is used for Opioid Overdose?
Naloxone
Which drug is used for Opioid detoxification and alcoholism?
Naltrexone
What is the MOA of Morphine?
Inhibits neurons in the CNS, GI and Spinal Cord (some Kappa activity in addition to Mu) and prevents release of substance P
What are the CNS effects of Morphine?
- Analgesia
- Drowsiness/ Itchy nose
- Euphoria and Dysphoria
- Nausea and Vomiting
What is a sign of Opioid Intoxication?
Miosis (excitement at Edinger-Westphal)
What is the cause of death in Opioid overdose?
Respiratory Depression
What are the cardio effects of Morphine?
- Vasodilation
2. Orthostatic Hypotension
What is the GI effect of Morphine?
- Constipation (decreased motility, tone and secretions)
2. Increased anal sphincter tone and biliary pressure
What is the Endocrine effect of Morphine?
- Decreased LH and Testosterone
- Menstrual Irregularities
- Male Impotence
What effects of opioids are not effected by tolerance?
- Miosis
- Constipation
- Respiratory Depression
What are withdrawal symptoms of Morphine?
- Hyperalgesia
- Hyperventilation
- Dilation of Pupils
- Diarrhea
- Dysphoria
Which drugs potentiate effects of Morphine?
- Phenothiazines (increase sedative)
- MAOIs
- TCAs
- Amphetamine (increases analgesia)
What is the treatment for Opioid Poisoning?
- Ventillation
2. IV Antagonist (Naloxone)
What are the contraindications of opioid use?
- Liver Issues
- Respiratory Insufficiency (obesity, emphysema)
- Head injury
Which enzyme is important for the breakdown of Morphine into its active metabolites?
CYP2D6 (O-demethylation)
What metabolite can be detected in the urine of Heroin users?
6-monoacetylmorphine
Constipation and biliary spasms are a predominant side effect of which drug?
Methadone
What are the metabolites of Heroin that can cross the BBB (at a higher % than Morphine)?
Diacetylmorphine –> 6-monoacetlymorphine (causes effects) and Morphine (causes effects)
Lortab and Vicoden, which have a similar effectiveness to Morphine, are combinations of which drugs?
Hydrocodone + Acetaminophen
What is the delayed release form of Oxycodone?
Oxycontin (high abuse potential)
What is the extended release formula of Hydrocodone that has a high OD Potential?
Zohydro
Phenylpiperdine analgesics include which drugs?
Fentanyl + Analogs and Meperidine
The excitement at toxic doses of what opioid are not blocked by Naloxone?
Meperidine
Which combination of drugs can result in a severe reaction of excitation, delirium, hyperpyrexia, convulsions and respiratory depression?
Meperidine + MAOIs
Fentanyl is an analog of what drug?
Meperidine
Which drug for chronic pain produces less nausea than Morphine?
Fentanyl
Which fentanyl derivative is 6000x Morphine, used for surgical anesthesia and may –> respiratory depression and chest wall rigidity?
Sufentanil
Which fentanyl derivative is short acting?
Remifentanil
Which drug is ineffective in slow metabolizers but may lead to overdose in rapid metabolizers, and which enzyme is responsible for its breakdown to Morphine?
Codein, CYP2D6
Which opioid drug is good for its low potential of dependance and weak analgesic effects?
Propoxyphene
What is the use/effects of Pentazocine?
Analgesia, sedation, respiratory depression; used for acute pain
What is a risk of Pentazocine?
May –> withdrawal in patients who are taking Opioids
What is Talwin?
A Combination drug including Pentazocine that is good to prevent drug abuse
What drug may lead to euphoria in patients taking Pentazocine?
Tripelennamine (antihistamine)
What drug is good for pregnant addicts?
Buprenorphine
Which drug, that is not an opioid, bind to the opioid receptor to inhibit NE and 5HT release in the treatment of neuropathic pain?
Tramadol
Which drug may lead to immediate/violent severe opioid withdrawal symptoms?
Naloxone
What is Dextromethorphan?
A synthetic derivative of morphine that suppresses cough
What is the function of Diphenoxylate and Loperamide?
Antidiarrheal; acting on mu receptors of the GI nerve plexus
What is Clonidine?
An Alpha 2 Adrenergic Agonist
What is the MOA of Clonidine?
–> increased NE which inhibits pain by activating receptors in the Dorsal Horn and Primary Afferents
What is the use of Clonidine?
Neuropathic or Cancer Pain
What antidepressants may be used for pain?
- TCAs (Amitriptyline)
2. SNRIs (Venlafaxine and Duloxetine)
What is the MOA of antidepressants in treating pain?
Inhibit the reuptake of NE and 5HT –> promotes NE activation of neurons in the dorsal horn and primary afferents; also may be important in perception of pain
What is the use of TCAs and SNRIs?
Neuropathic Pain
What are the anti-epileptics used for pain?
- Alpha-2-Delta Ligands (Gabapentin and Pregabalin)
2. Carbamazepine
What is the MOA of Gabapentin and Pregabalin?
Reduce activation of VG-Ca Channels
What is the MOA of Carbamazepine?
Stabilizes inactive state of VG-Na Channels
What is the use of Carbamazepine?
Neuropathic Pain and Trigeminal Neuralgia
What is the use of Gabapentin and Pregabalin?
- Post-Herpetic Neuralgia
- Diabetic Neuropathy
- Fibromyalgia
How does the onset of Pregabalin compare to Gabapentin?
It is faster
What are Lidocaine and Capsaicin?
Topical anesthetics (TRPV1 Antagonist)
What is Katamine?
An NMDA Antagonist that decreases Glutamate signaling