Adrenergic Drugs Flashcards

(33 cards)

1
Q

Norepinephrine

A

@ *Alpha

e.g. Levophed: no longer used; was used to treat shock by Vasoconstriction, but also Constricted Renal Vessels, causing Renal Failure by Kidney Shock.

\_\_\_\_\_\_\_\_\_\_\_
Norepinephrine: Alpha mostly
1) Peripheral Vasoconstriction
=> Increases Peripheral Resistance
=> Increases Blood Pressure
=> Increases MAP
(Mean Arterial Pressure)
2) Results in Reflex Bradycardia (Baroreflex)
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2
Q

Epinephrine

A

@ *Alpha, *Beta-1, *Beta-2

1) DOC: *Acute Hypersensitivity Reactions
(e.g. *Anaphylactic Shock)
Via injection primarily.
(Beta1: Stimulate Heart,
Beta2: Bronchodilation,
Alpha1: Vasoconstriction to Elevate Blood Pressure)
(Note: High Doses of Epi, or Epi given to a Hypotensive person will cause greater Alpha

2) *Heart Block and Cardiac Arrest (Emergency Use)

3) *Vasoconstrictor in *Local Anesthetic Preps
(e.g. Novocaine)
(Alpha1 Vasoconstriction)
(Keeps the anesthetic localized for longer, preventing systemic toxicity)

\_\_\_\_\_\_\_\_\_\_\_\_
Epinephrine:
1) Beta-2 Vasodilation (Skeletal muscle bed is large vascular bed)
=> Decreases Peripheral Resistance
=> Decreases Diastolic BP
2) Beta-1 Cardiac Stimulation
=> Increases Cardiac Output
=> Increases Heart Rate
=> Increases Systolic BP
3) Overall No change in MAP
(Mean Arterial Pressure)
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3
Q

Dopamine

A

(precursor of NE and Epi)
@ Alpha-1, Beta-1, DA

*Important Drug for Shock:
_
Maintains Renal Blood Flow!
_While Stimulating Heart and Vasoconstriction.

(DA treats shock while protecting Kidney;
NE treats shock while shocking Kidney.)
(D1 Receptor: Renal Arterial Dilation)

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4
Q

Isoproterenol

A

@ *All Beta Receptors
(Non-selective Beta Agonist)

_Used to be used to treat Asthma via Bronchodilation, but had Adverse Effects: Stimulation of Heart: Arrhythmias and Heart Attacks at young age.

(It has helped us Distinguish Alpha from Beta Receptors.)

__________

Isoproterenol: 
1) Beta-2 Vasodilation
(particularly @ Skeletal muscle bed, which is a very large vascular bed)
=> Decreases Peripheral Resistance (Markedly)
=> Decreases Diastolic BP
=> Decreases MAP 
(Mean Arterial Pressure)
2) Beta-1 Cardiac Stimulation
=> Increases Cardiac Output
=> Increases Heart Rate
=> Initial Increase in Systolic BP (transient)
3) => Overall Decreases in BP
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5
Q

Albuterol

A

Direct-Acting Sympathomimetics

Beta-2 Agonists

  • *Major Drugs in Class:
    1) *Albuterol (Ventolin)
    2) *Salmeterol (Serevent, in Advair),
    3) *Ritodrine (Yutopar)

Therapeutics:
1) Asthma (Bronchodilation)
2) Premature Labor
(
Uterine Relaxation)

Adverse Effects:
1) *Tremors 
(*Beta-2 @ Skeletal Muscle)
2) *Cardiac Stimulation 
(*Beta-1)
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6
Q

Salmeterol

A

Direct-Acting Sympathomimetics

Beta-2 Agonists

  • *Major Drugs in Class:
    1) *Albuterol (Ventolin)
    2) *Salmeterol (Serevent, in Advair),
    3) *Ritodrine (Yutopar)

Therapeutics:
1) Asthma (Bronchodilation)
2) Premature Labor
(
Uterine Relaxation)

Adverse Effects:
1) *Tremors 
(*Beta-2 @ Skeletal Muscle)
2) *Cardiac Stimulation 
(*Beta-1)
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7
Q

Ritodrine

A

Direct-Acting Sympathomimetics

Beta-2 Agonists

  • *Major Drugs in Class:
    1) *Albuterol (Ventolin)
    2) *Salmeterol (Serevent, in Advair),
    3) *Ritodrine (Yutopar)

Therapeutics:
1) Asthma (Bronchodilation)
2) Premature Labor
(
Uterine Relaxation)

Adverse Effects:
1) *Tremors 
(*Beta-2 @ Skeletal Muscle)
2) *Cardiac Stimulation 
(*Beta-1)
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8
Q

Dobutamine

A

Direct-Acting Sympathomimetics

Beta-1 Agonist

Dobutamine (Prototype Drug)

Therapeutics:

1) *Cardiovascular Effects
2) Cardiac Decompensation,
* Acute CHF (
Beta-1, Alpha-1)

Adverse Effect (Same Mechs):

1) *Arrhythmia (Beta-1)
2) *Hypertension (Alpha-1)

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9
Q

Mirabegron (Myrbetriq)

A

Direct-Acting Sympathomimetics

Beta-3 Agonist

Option if Muscarinic Blockers don’t work or can’t tolerate side effects.

Use:
1) Treat Overactive Bladder
(Beta-3: Relaxes Smooth Muscle @ Bladder)

Adverse Effects:
1) Mild Cardiovascular Stimulation (Beta-1)

Most Beta-3 mediate Metabolic effects: Lipolysis @ Adipose tissue

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10
Q

Phenylephrine

A

Direct-Acting Sympathomimetics

Alpha-1 Agonists

1) *Phenylephrine (NeoSynephrine)
2) *Oxymetazoline (Afrin)
3) *Pseudoephedrine (Sudafed)

Therapeutics:

1) *Nasal Decongestant
2) *Pressor (Increase BP)

Adverse Effects:
1) *Hypertension with *Reflex Bradycardia
(Reflex via baroreceptors in Carotid Sinus and Aortic Arch)

2) *Rebound Congestion
(rhinitis medicamentosa)

3) *Urinary Retention
(Urinary Sphincter Contraction)
(esp. Middle-aged/Older Males or if have enlarged prostate)

4) * CNS Stimulation:
e. g. *Insomnia

(Vasoconstriction in Nasal Mucosa, decreasing blood flow, which decreases leakage of fluids into tissues)

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11
Q

Oxymetazoline

A

Direct-Acting Sympathomimetics

Alpha-1 Agonists

1) *Phenylephrine (NeoSynephrine)
2) *Oxymetazoline (Afrin)
3) *Pseudoephedrine (Sudafed)

Therapeutics:

1) *Nasal Decongestant
2) *Pressor (Increase BP)

Adverse Effects:
1) *Hypertension with *Reflex Bradycardia
(Reflex via baroreceptors in Carotid Sinus and Aortic Arch)

2) *Rebound Congestion
(rhinitis medicamentosa)

3) *Urinary Retention
(Urinary Sphincter Contraction)
(esp. Middle-aged/Older Males or if have enlarged prostate)

4) * CNS Stimulation:
e. g. *Insomnia

(Vasoconstriction in Nasal Mucosa, decreasing blood flow, which decreases leakage of fluids into tissues)

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12
Q

Pseudoephedrine

A

Direct-Acting Sympathomimetics

Alpha-1 Agonists

1) *Phenylephrine (NeoSynephrine)
2) *Oxymetazoline (Afrin)
3) *Pseudoephedrine (Sudafed)

Therapeutics:

1) *Nasal Decongestant
2) *Pressor (Increase BP)

Adverse Effects:
1) *Hypertension with *Reflex Bradycardia
(Reflex via baroreceptors in Carotid Sinus and Aortic Arch)

2) *Rebound Congestion
(rhinitis medicamentosa)

3) *Urinary Retention
(Urinary Sphincter Contraction)
(esp. Middle-aged/Older Males or if have enlarged prostate)

4) * CNS Stimulation:
e. g. *Insomnia

(Vasoconstriction in Nasal Mucosa, decreasing blood flow, which decreases leakage of fluids into tissues)

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13
Q

Clonidine

A

Direct-Acting Sympathomimetics

Alpha-2 Agonists

1) *Clonidine (Catapres)
2) *Tizanidine (Zanaflex)
3) *Alpha-methyldopa

Therapeutics:
1) *Hypertension
(Acts centrally in Medulla of Brainstem to inhibit Sympathetics there)

2) *Glaucoma
(Reduces Formation of Aqueous humor, reducing intraocular pressure)

3) *Spasticity due to Neuropathy
(e.g. Cerebral Palsy)
(Acts in Spinal cord to reduce firing to motor neurons there)

4) *ADHD
(Not first-line. Aren’t as effective as Central Stimulants.)

Adverse Effects:

1) *Sedation
2) *Muscle Weakness
3) **Rebound Hypertension
4) Inability to Ejaculate

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14
Q

Tizanidine

A

Direct-Acting Sympathomimetics

Alpha-2 Agonists

1) *Clonidine (Catapres)
2) *Tizanidine (Zanaflex)

Therapeutics:
1) *Hypertension
(Acts centrally in Medulla of Brainstem to inhibit Sympathetics there)

2) *Glaucoma
(Reduces Formation of Aqueous humor, reducing intraocular pressure)

3) *Spasticity due to Neuropathy
(e.g. Cerebral Palsy)
(Acts in Spinal cord to reduce firing to motor neurons there)

4) *ADHD
(Not first-line. Aren’t as effective as Central Stimulants.)

Adverse Effects:

1) *Sedation
2) *Muscle Weakness
3) **Rebound Hypertension
4) Inability to Ejaculate

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15
Q

Amphetamine,

Methamphetamine

A

Indirect-Acting Sympathomimetics

Stimulate Release

  • Amphetamine,
  • Methamphetamine (Greater CNS Activity)

Therapeutics:

1) *Narcolepsy
2) *ADHD

Adverse Effects:

1) *Cardiovascular: Hypertension, Tachycardia
2) *Tremor
3) *Convulsions
4) *Dependence (chronic use)
5) *Psychosis (chronic use)

Tolerance Development: Tachyphylaxis

Note:
***Interaction of These with MAO Inhibitors can cause Hypertensive Crisis!!!

*Tolerance Development: Tachyphylaxis
= Rapid Tolerance with Repeated administration of drug
_Due to Depletion of NE and Rapid Desensitivity of the Receptors on the postsynaptic/effector cell.

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16
Q

Ephedrine

A

Indirect-Acting Sympathomimetics

Stimulate Release

*Mixed Action:
_Direct Action @ Alpha and Beta
_AND Indirect Action to Release NE
_Similar to Amphetamines, but milder.

Note:
***Interaction of These with MAO Inhibitors can cause Hypertensive Crisis!!!

*Tolerance Development: Tachyphylaxis
= Rapid Tolerance with Repeated administration of drug
_Due to Depletion of NE and Rapid Desensitivity of the Receptors on the postsynaptic/effector cell.

17
Q

Tyramine

A

Indirect-Acting Sympathomimetics

Stimulate Release

Tyramine:
_
Found in Food
(e.g. beer, brewer’s yeast, red wine, aged cheeses, smoked or pickled fish, fermented sausage such as pepperoni and salami)
_Not a pharm drug

Note:
***Interaction of These with MAO Inhibitors can cause Hypertensive Crisis!!!

*Tolerance Development: Tachyphylaxis
= Rapid Tolerance with Repeated administration of drug
_Due to Depletion of NE and Rapid Desensitivity of the Receptors on the postsynaptic/effector cell.

18
Q

Cocaine

A

Indirect-Acting Sympathomimetics

Inhibit NE Reuptake

(NE Reuptake by Neuron is 70-80%)

1) *Cocaine (Also Inhibits *Dopamine Reuptake)

2) *Tricyclic Antidepressants
_Uses: Depression, Pain Syndromes.

19
Q

Tricyclic Antidepressants

A

Indirect-Acting Sympathomimetics

Inhibit NE Reuptake

(NE Reuptake by Neuron is 70-80%)

1) *Cocaine (Also Inhibits *Dopamine Reuptake)

2) *Tricyclic Antidepressants
_Uses: Depression, Pain Syndromes.

20
Q

MAO Inhibitors

A

Indirect-Acting Sympathomimetics

Inhibit Metabolism

*MAO Inhibitors:
1) *Selegiline:
*Inhibits MAO-b.
Increases DA in Brain.

Uses:
_Depression (isozyme A)
_Parkinson’s (isozyme B)

21
Q

Selegiline

A

Indirect-Acting Sympathomimetics

Inhibit Metabolism

*MAO Inhibitors:
1) *Selegiline:
*Inhibits MAO-b.
Increases DA in Brain.

Uses:
_Depression (isozyme A)
_Parkinson’s (isozyme B)

22
Q

COMT Inhibitors

A

Indirect-Acting Sympathomimetics

Inhibit Metabolism

*COMT:
Uses: Parkinson’s
Increases DA in Brain.

23
Q

Propranolol

A

Beta Antagonists
(Beta Blockers)

1) *Propranolol 
(Non-Selective) (prototype)
2) *Metoprolol 
(Beta-1 Selective)
3) *Atenolol 
(Beta-1 Selective)

Therapeutics:
1) Hypertension (Chronic)
_
Less Effective in Black patients
_First-line for uncomplicated Essential Hypertension

2) Arrhythmia (Metoprolol)

3) Angina (Atenolol)
_*Pindolol (non-selective, partial agonist): Less Rebound Angina upon abrupt cessation of treatment

4) *CHF (Chronic, Stable type)
5) *Post-MI

6) Tremor of Peripheral origin
(Blocks Beta-2 @ Skeletal Muscle)
(
Propranolol most frequently used)

7) Glaucoma (Timolol, non-selective)
(Reduce Aqueous Humor Formation)

8) *Migraine Prophylaxis (Propranolol)

9) Hyperthyroidism:
(Propranolol)
_
Blocks the Cardiac Manifestations due to Beta Receptor Supersensitivity

Adverse Effects:
1) *Bronchoconstriction 
(Beta-2 Blockage)
_*Asthma Patients: 
Prefer Beta-1 Selective agent

2) Hypoglycemia
(Compensatory hyperglycemic effect of Epinephrine in insulin-induced Hypoglycemia is Blocked by Beta-1 Blockage @ Liver
_Sweating is the Only symptom of Hypoglycemia that Remains.
(Lose symptoms of tremor, palpitations)
_Beta-1 Selective agents preferred in Diabetic patients.)

3) Nightmares/Sleep Disturbances, Fatigue, Sedation
_Propranolol has High Lipid Solubility. Atenolol has less.

4) Contraindicated in Unstable/Decompensated CHF or Acute CHF
_Will exacerbate it

24
Q

Metoprolol

A

Beta Antagonists
(Beta Blockers)

1) *Propranolol 
(Non-Selective) (prototype)
2) *Metoprolol 
(Beta-1 Selective)
3) *Atenolol 
(Beta-1 Selective)

Therapeutics:
1) Hypertension (Chronic)
_
Less Effective in Black patients
_First-line for uncomplicated Essential Hypertension

2) Arrhythmia (Metoprolol)

3) Angina (Atenolol)
_*Pindolol (non-selective, partial agonist): Less Rebound Angina upon abrupt cessation of treatment

4) *CHF (Chronic, Stable type)
5) *Post-MI

6) Tremor of Peripheral origin
(Blocks Beta-2 @ Skeletal Muscle)
(
Propranolol most frequently used)

7) Glaucoma (Timolol, non-selective)
(Reduce Aqueous Humor Formation)

8) *Migraine Prophylaxis (Propranolol)

9) Hyperthyroidism:
(Propranolol)
_
Blocks the Cardiac Manifestations due to Beta Receptor Supersensitivity

Adverse Effects:
1) *Bronchoconstriction 
(Beta-2 Blockage)
_*Asthma Patients: 
Prefer Beta-1 Selective agent

2) Hypoglycemia
(Compensatory hyperglycemic effect of Epinephrine in insulin-induced Hypoglycemia is Blocked by Beta-1 Blockage @ Liver
_Sweating is the Only symptom of Hypoglycemia that Remains.
(Lose symptoms of tremor, palpitations)
_Beta-1 Selective agents preferred in Diabetic patients.)

3) Nightmares/Sleep Disturbances, Fatigue, Sedation
_Propranolol has High Lipid Solubility. Atenolol has less.

4) Contraindicated in Unstable/Decompensated CHF or Acute CHF
_Will exacerbate it

25
Atenolol
Beta Antagonists (Beta Blockers) ``` 1) *Propranolol (Non-Selective) (prototype) 2) *Metoprolol (Beta-1 Selective) 3) *Atenolol (Beta-1 Selective) ``` Therapeutics: 1) *Hypertension (Chronic) _*Less Effective in Black patients _First-line for uncomplicated Essential Hypertension 2) *Arrhythmia (*Metoprolol) 3) *Angina (*Atenolol) _*Pindolol (non-selective, partial agonist): Less Rebound Angina upon abrupt cessation of treatment 4) *CHF (Chronic, Stable type) 5) *Post-MI 6) *Tremor of Peripheral origin (Blocks Beta-2 @ Skeletal Muscle) (*Propranolol most frequently used) 7) *Glaucoma (*Timolol, non-selective) (Reduce Aqueous Humor Formation) 8) *Migraine Prophylaxis (Propranolol) 9) *Hyperthyroidism: (Propranolol) _*Blocks the Cardiac Manifestations due to Beta Receptor Supersensitivity ``` Adverse Effects: 1) *Bronchoconstriction (Beta-2 Blockage) _*Asthma Patients: Prefer Beta-1 Selective agent ``` 2) Hypoglycemia (Compensatory hyperglycemic effect of Epinephrine in insulin-induced Hypoglycemia is Blocked by Beta-1 Blockage @ Liver _Sweating is the Only symptom of Hypoglycemia that Remains. (Lose symptoms of tremor, palpitations) _Beta-1 Selective agents preferred in Diabetic patients.) 3) Nightmares/Sleep Disturbances, Fatigue, Sedation _Propranolol has High Lipid Solubility. Atenolol has less. 4) Contraindicated in Unstable/Decompensated CHF or Acute CHF _Will exacerbate it
26
Pindolol
Beta Antagonists (Beta Blockers) ``` 1) *Propranolol (Non-Selective) (prototype) 2) *Metoprolol (Beta-1 Selective) 3) *Atenolol (Beta-1 Selective) ``` Therapeutics: 1) *Hypertension (Chronic) _*Less Effective in Black patients _First-line for uncomplicated Essential Hypertension 2) *Arrhythmia (*Metoprolol) 3) *Angina (*Atenolol) _*Pindolol (non-selective, partial agonist): Less Rebound Angina upon abrupt cessation of treatment 4) *CHF (Chronic, Stable type) 5) *Post-MI 6) *Tremor of Peripheral origin (Blocks Beta-2 @ Skeletal Muscle) (*Propranolol most frequently used) 7) *Glaucoma (*Timolol, non-selective) (Reduce Aqueous Humor Formation) 8) *Migraine Prophylaxis (Propranolol) 9) *Hyperthyroidism: (Propranolol) _*Blocks the Cardiac Manifestations due to Beta Receptor Supersensitivity ``` Adverse Effects: 1) *Bronchoconstriction (Beta-2 Blockage) _*Asthma Patients: Prefer Beta-1 Selective agent ``` 2) Hypoglycemia (Compensatory hyperglycemic effect of Epinephrine in insulin-induced Hypoglycemia is Blocked by Beta-1 Blockage @ Liver _Sweating is the Only symptom of Hypoglycemia that Remains. (Lose symptoms of tremor, palpitations) _Beta-1 Selective agents preferred in Diabetic patients.) 3) Nightmares/Sleep Disturbances, Fatigue, Sedation _Propranolol has High Lipid Solubility. Atenolol has less. 4) Contraindicated in Unstable/Decompensated CHF or Acute CHF _Will exacerbate it
27
Timolol
Beta Antagonists (Beta Blockers) ``` 1) *Propranolol (Non-Selective) (prototype) 2) *Metoprolol (Beta-1 Selective) 3) *Atenolol (Beta-1 Selective) ``` Therapeutics: 1) *Hypertension (Chronic) _*Less Effective in Black patients _First-line for uncomplicated Essential Hypertension 2) *Arrhythmia (*Metoprolol) 3) *Angina (*Atenolol) _*Pindolol (non-selective, partial agonist): Less Rebound Angina upon abrupt cessation of treatment 4) *CHF (Chronic, Stable type) 5) *Post-MI 6) *Tremor of Peripheral origin (Blocks Beta-2 @ Skeletal Muscle) (*Propranolol most frequently used) 7) *Glaucoma (*Timolol, non-selective) (Reduce Aqueous Humor Formation) 8) *Migraine Prophylaxis (Propranolol) 9) *Hyperthyroidism: (Propranolol) _*Blocks the Cardiac Manifestations due to Beta Receptor Supersensitivity ``` Adverse Effects: 1) *Bronchoconstriction (Beta-2 Blockage) _*Asthma Patients: Prefer Beta-1 Selective agent ``` 2) Hypoglycemia (Compensatory hyperglycemic effect of Epinephrine in insulin-induced Hypoglycemia is Blocked by Beta-1 Blockage @ Liver _Sweating is the Only symptom of Hypoglycemia that Remains. (Lose symptoms of tremor, palpitations) _Beta-1 Selective agents preferred in Diabetic patients.) 3) Nightmares/Sleep Disturbances, Fatigue, Sedation _Propranolol has High Lipid Solubility. Atenolol has less. 4) Contraindicated in Unstable/Decompensated CHF or Acute CHF _Will exacerbate it
28
Prazosin
Alpha-1 Antagonists 1) *Prazosin (Prototype) 2) *Tamsulosin (Selective Alpha-1) 3) *Labetalol (Competitive Block @ both Alpha 1 and Beta) 4) *Carvedilol (Competitive Block @ both Alpha 1 and Beta) Therapeutics: 1) *Chronic Hypertension (*Prazosin) (p.o.) (emergency: inj.) 2) *Benign Prostatic Hypertrophy (BPH): (*Tamsulosin) _Relax Urinary Sphincter, Promote Urine Flow Adverse Effects: 1) *Postural Hypotension (Very Marked) _Due to Blockage of Reflex Vasoconstriction 2) *Reflex Tachycardia 3) Impaired Ejaculation (More of an issue in Middle-aged men) 4) Nasal Stuffiness _Due to Dilation of Nasal Mucosal Vessels)
29
Tamsulosin
Alpha-1 Antagonists 1) *Prazosin (Prototype) 2) *Tamsulosin (Selective Alpha-1) 3) *Labetalol (Competitive Block @ both Alpha 1 and Beta) 4) *Carvedilol (Competitive Block @ both Alpha 1 and Beta) Therapeutics: 1) *Chronic Hypertension (*Prazosin) (p.o.) (emergency: inj.) 2) *Benign Prostatic Hypertrophy (BPH): (*Tamsulosin) _Relax Urinary Sphincter, Promote Urine Flow Adverse Effects: 1) *Postural Hypotension (Very Marked) _Due to Blockage of Reflex Vasoconstriction 2) *Reflex Tachycardia 3) Impaired Ejaculation (More of an issue in Middle-aged men) 4) Nasal Stuffiness _Due to Dilation of Nasal Mucosal Vessels)
30
Labetalol
Alpha-1 Antagonists 1) *Prazosin (Prototype) 2) *Tamsulosin (Selective Alpha-1) 3) *Labetalol (Competitive Block @ both Alpha 1 and Beta) 4) *Carvedilol (Competitive Block @ both Alpha 1 and Beta) Therapeutics: 1) *Chronic Hypertension (*Prazosin) (p.o.) (emergency: inj.) 2) *Benign Prostatic Hypertrophy (BPH): (*Tamsulosin) _Relax Urinary Sphincter, Promote Urine Flow Adverse Effects: 1) *Postural Hypotension (Very Marked) _Due to Blockage of Reflex Vasoconstriction 2) *Reflex Tachycardia 3) Impaired Ejaculation (More of an issue in Middle-aged men) 4) Nasal Stuffiness _Due to Dilation of Nasal Mucosal Vessels)
31
Reserpine
Drugs That Decrease NE @ Nerve Terminal 1) *Direct Inhibition of NE Synthesis 2) *Inhibition of Intra-Neuronal Storage of Catecholamines: _*Reserpine: Inhibits Transport of NE from Cytosol to Vesicle. Leads to Gradual Depletion of NE (and 5-HT) Stores. _Antihypertensive, but little use now. Major side effects: lethargy, diarrhea, depression (very long lasting) 3) *Prevention of Normal Transmitter Release
32
Alpha-Methyldopa
Direct-Acting Sympathomimetics Alpha-2 Agonists 1) *Clonidine (Catapres) 2) *Tizanidine (Zanaflex) 3) *Alpha-methyldopa Therapeutics: 1) *Hypertension (Acts centrally in Medulla of Brainstem to inhibit Sympathetics there) 2) *Glaucoma (Reduces Formation of Aqueous humor, reducing intraocular pressure) 3) *Spasticity due to Neuropathy (e.g. Cerebral Palsy) (Acts in Spinal cord to reduce firing to motor neurons there) 4) *ADHD (Not first-line. Aren't as effective as Central Stimulants.) Adverse Effects: 1) *Sedation 2) *Muscle Weakness 3) **Rebound Hypertension 4) Inability to Ejaculate
33
Carvedilol
Alpha-1 Antagonists 1) *Prazosin (Prototype) 2) *Tamsulosin (Selective Alpha-1) 3) *Labetalol (Competitive Block @ both Alpha 1 and Beta) 4) *Carvedilol (Competitive Block @ both Alpha 1 and Beta) Therapeutics: 1) *Chronic Hypertension (*Prazosin) (p.o.) (emergency: inj.) 2) *Benign Prostatic Hypertrophy (BPH): (*Tamsulosin) _Relax Urinary Sphincter, Promote Urine Flow Adverse Effects: 1) *Postural Hypotension (Very Marked) _Due to Blockage of Reflex Vasoconstriction 2) *Reflex Tachycardia 3) Impaired Ejaculation (More of an issue in Middle-aged men) 4) Nasal Stuffiness _Due to Dilation of Nasal Mucosal Vessels)