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Guanabenz Side Effects

The most commonly reported side effects of guanabenz include blood creatinine increased, dizziness, and hypertension, based on 149 FDA adverse event reports from 2004 to 2025.

Guanabenz side effects

Percentages show how often each reaction appears relative to total reports for guanabenz.

1
Blood Creatinine Increased8.1%12
2
Dizziness4.7%7
3
Hypertension4.7%7
4
Urinary Tract Infection4.7%7
5
Renal Failure4.7%7
6
Fall4.0%6
7
Renal Failure Acute4.0%6
8
Depressed Level Of Consciousness4.0%6
9
Hyperkalaemia4.0%6
10
Thrombocytopenia4.0%6
11
Oedema Peripheral3.4%5
12
Pneumonia3.4%5
13
Blood Urea Increased3.4%5
14
Glycosylated Haemoglobin Increased3.4%5
15
Cerebral Infarction3.4%5

These are voluntary reports and do not establish that guanabenz caused these reactions.

Report severity

94.6%Serious141 reports
57.0%Hospitalizations85 reports
14.8%Fatal22 reports

Seriousness is determined by the reporter, not by OpenClaim.

Guanabenz drug interactions

Other drugs that appear in adverse event reports alongside guanabenz. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Nifedipine6.0%9
2
Valsartan6.0%9
3
Amlodipine5.4%8
4
Telmisartan5.4%8
5
Aspirin5.4%8
6
Icodextrin4.7%7
7
Furosemide4.7%7
8
Darbepoetin-alfa4.7%7
9
Allopurinol4.0%6
10
Carvedilol3.4%5
11
Doxazosin-mesylate2.7%4
12
Methoxy-polyethylene-glycol-epoetin-beta2.7%4
13
Pembrolizumab2.7%4
14
Ezetimibe2.0%3
15
Alendronate-sodium2.0%3

Taken alongside

1
Amlodipine22.1%33
2
Furosemide21.5%32
3
Nifedipine16.8%25
4
Aspirin13.4%20
5
Valsartan12.1%18
6
Atorvastatin-calcium10.1%15
7
Allopurinol8.7%13
8
Glimepiride8.7%13
9
Calcium-carbonate8.1%12
10
Spironolactone6.7%10
11
Insulin6.7%10
12
Telmisartan6.0%9
13
Lansoprazole6.0%9
14
Levothyroxine-sodium5.4%8
15
Doxazosin-mesylate5.4%8

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports guanabenz side effects

38.9% of guanabenz adverse event reports involve female patients and 58.4% involve male patients. The largest age group is elderly at 71%. These figures reflect who reports side effects, not underlying risk.

Sex

Female38.9%
Male58.4%
Unknown2.7%

Age group

< 20.0%
2–110.0%
12–170.0%
18–6429.4%
65+70.6%

What is guanabenz used for

Conditions and purposes for which patients were taking guanabenz when the adverse event was reported.

Blood Pressure IncreasedDrug Use For Unknown IndicationEssential HypertensionEssential HypertensionHypertensionHypertensionNephrosclerosisProduct Used For Unknown IndicationProduct Used For Unknown IndicationRenovascular Hypertension

Guanabenz brand names and reporting trend

Guanabenz is sold under the brand name Guanabenz Acetate.

Brand names

Guanabenz Acetate41

Quarterly reports (20042025)

200520152025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking guanabenz with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.