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Brand Name :
Ismelin
Synonyms :
guanethidine
Class :
adrenergic Neurone Blocking Drugs
Brand Name :
Ismelin
Synonyms :
guanethidine
Class :
adrenergic Neurone Blocking Drugs
Dosage Forms & Strengths
Injectable solution
10mg/1ml
It is recommended to give one injection of 10–20 mg. This results in a fall of blood pressure in 30 minutes, with a maximum at 1-2 hours, and maintains stability for 4 to 6 hours. Three hours is needed between doses if an additional 10–20 mg dose is determined to be necessary
Safety and efficacy were not established
Refer to the adult dosing regimen
guanethidine: they may increase the CNS depressant effect of CNS Depressants
guanethidine: they may increase the CNS depressant effect of CNS Depressants
guanethidine: they may increase the CNS depressant effect of CNS Depressants
guanethidine: they may increase the CNS depressant effect of CNS Depressants
guanethidine: they may increase the CNS depressant effect of CNS Depressants
may increase the toxic effect of Monoamine Oxidase Inhibitors
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
may increase the hypoglycemic effect
may increase the hypoglycemic effect
may increase the hypoglycemic effect
may increase the hypoglycemic effect
may increase the hypoglycemic effect
it increases the arrhythmogenic effect of sympathomimetics
it increases the arrhythmogenic effect of sympathomimetics
it increases the arrhythmogenic effect of sympathomimetics
it increases the arrhythmogenic effect of sympathomimetics
it increases the arrhythmogenic effect of sympathomimetics
may have an increased arrhythmogenic effect when combined with sympathomimetics
may have an increased arrhythmogenic effect when combined with sympathomimetics
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
may decrease the therapeutic effect when combined with guanethidine
may decrease the therapeutic effect when combined with guanethidine
may decrease the therapeutic effect when combined with guanethidine
may decrease the therapeutic effect when combined with guanethidine
may decrease the therapeutic effect when combined with guanethidine
it may diminish the excretion rate when combined with permethrin, resulting in an enhanced serum level
it increases the effect of hypoglycemia on antidiabetic agents
it increases the effect of hypoglycemia on antidiabetic agents
it increases the effect of hypoglycemia on antidiabetic agents
The therapeutic efficacy of guanethidine may be reduced by estrogen derivative
The therapeutic efficacy of guanethidine may be reduced by estrogen derivative
bazedoxifene/conjugated estrogens
The therapeutic efficacy of guanethidine may be reduced by estrogen derivative
The therapeutic efficacy of guanethidine may be reduced by estrogen derivative
The therapeutic efficacy of guanethidine may be reduced by estrogen derivative
The efficacy of guanethidine could be reduced by the presence of antipsychotic agents
The efficacy of guanethidine could be reduced by the presence of antipsychotic agents
The efficacy of guanethidine could be reduced by the presence of antipsychotic agents
The efficacy of guanethidine could be reduced by the presence of antipsychotic agents
The efficacy of guanethidine could be reduced by the presence of antipsychotic agents
guanethidine: they may increase the hypotensive effect of loop diuretics
guanethidine: they may increase the hypotensive effect of loop diuretics
guanethidine: they may increase the hypotensive effect of loop diuretics
guanethidine : it may increase the toxic effect of Methemoglobinemia Associated Agents
guanethidine : it may increase the toxic effect of Methemoglobinemia Associated Agents
guanethidine : it may increase the toxic effect of Methemoglobinemia Associated Agents
guanethidine : it may increase the toxic effect of Methemoglobinemia Associated Agents
guanethidine : it may increase the toxic effect of Methemoglobinemia Associated Agents
it increases the effect of hypoglycemia of antidiabetic agents
it increases the effect of hypoglycemia of antidiabetic agents
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
norepinephrine reuptake inhibitors decrease the effect of guanethidine
may increase the tachycardiac effect of sympathomimetic drugs
may increase the tachycardiac effect of sympathomimetic drugs
may increase the hypoglycaemic effect of anti-diabetic agents
may increase the arrhythmogenic effect of sympathomimetics
may increase the arrhythmogenic effect of sympathomimetics
may decrease the therapeutic effect of Anticholinergic Agents
Actions and spectrum:
Frequency not defined
Abdominal distension
Angina
Blurred vision
Cardiac failure
Dermatitis
Dizziness
Exacerbation of claudication
Hair loss
Increased BUN
Leucopenia
Nasal congestion
Oedema
Parotid gland swelling
Sick-sinus syndrome
Tiredness
Uraemia
Anaemia
Asthma
Bradycardia
Depression
Diarrhoea
Dry mouth
Failure of ejaculation
Headache
Lethargy
Myalgia
Nausea
Paraesthesia
Postural hypotension
Thrombocytopenia
Tremor
Vomiting
Black Box Warning:
There is no specific black box warning associated with guanethidine.
Contraindication/Caution:
Contraindication:
Caution:
Comorbidities:
Pregnancy consideration: pregnancy category C
Lactation: excreted into human milk: yes
Pregnancy category:
Pharmacology:
guanethidine is an antihypertensive medication with a unique mechanism of action within the sympathetic nervous system. As a sympatholytic agent, guanethidine works by entering sympathetic nerve endings and replacing norepinephrine, a neurotransmitter responsible for “fight or flight” response, in storage vesicles.
Once taken up by the nerve endings, guanethidine interferes with the release of norepinephrine during sympathetic stimulation, effectively blocking the transmission of nerve signals.
This disruption leads to a reduction in sympathetic outflow, causing vasodilation and a decrease in heart rate, contributing to lowered blood pressure. Despite its historical use, guanethidine has fallen out of favor as a first-line treatment for hypertension due to side effects and the availability of more effective antihypertensive medications.
Pharmacodynamics:
Pharmacokinetics:
Administration:
Patient information leaflet
Generic Name: guanethidine
Pronounced: (gwah-NEH-thi-deen)
Why do we use guanethidine?
guanethidine was traditionally used to lower blood pressure in hypertensive patients. Its mechanism of action involves inhibiting the norepinephrine release from sympathetic nerve endings, leading to vasodilation and a reduction in blood pressure.
guanethidine’s ability to block sympathetic nerve transmission made it a potential treatment for certain disorders associated with overactivity of the sympathetic nervous system. However, due to its side effect profile and the availability of more effective and better-tolerated medications, its use for these purposes is limited.
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