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Methyltestosterone Side Effects

The most commonly reported side effects of methyltestosterone include drug interaction, fatigue, and schizoaffective disorder, based on 350 FDA adverse event reports from 2004 to 2025. 6.3% of reports found the drug to be ineffective.

Methyltestosterone side effects

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

1
Drug Interaction10.9%38
2
Fatigue10.6%37
3
Schizoaffective Disorder10.6%37
4
Electrocardiogram Qt Prolonged10.6%37
5
Drug Level Increased10.6%37
6
Headache9.4%33
7
Pyrexia8.3%29
8
Product Use Issue8.3%29
9
Nausea7.7%27
10
Dyspnoea7.4%26
11
Asthenia7.1%25
12
Insomnia6.9%24
13
Pain6.6%23
14
Arthralgia6.6%23
15
Off Label Use6.6%23

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

Report severity

70.9%Serious248 reports
29.4%Hospitalizations103 reports
5.7%Fatal20 reports

Seriousness is determined by the reporter, not by OpenClaim.

Methyltestosterone drug interactions

Other drugs that appear in adverse event reports alongside methyltestosterone. 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
Estrogens13.4%47
2
Levothyroxine-sodium8.9%31
3
Estradiol8.3%29
4
Acetaminophen8.0%28
5
Eszopiclone7.1%25
6
Testosterone6.9%24
7
Aripiprazole6.6%23
8
Brexpiprazole6.6%23
9
Ranitidine6.6%23
10
Clozapine6.3%22
11
Amlodipine6.3%22
12
Cholecalciferol6.0%21
13
Olanzapine5.7%20
14
Divalproex-sodium5.4%19
15
Phenylephrine5.4%19

Taken alongside

1
Acetaminophen18.6%65
2
Ergocalciferol16.0%56
3
Levothyroxine-sodium15.1%53
4
Diphenhydramine14.6%51
5
Albuterol14.3%50
6
Epinephrine14.3%50
7
Progesterone12.6%44
8
Prednisone11.7%41
9
Aspirin11.7%41
10
Montelukast-sodium10.9%38
11
Fluticasone9.4%33
12
Estradiol8.6%30
13
Loratadine8.3%29
14
Furosemide7.7%27
15
Omeprazole7.7%27

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 methyltestosterone side effects

73.1% of methyltestosterone adverse event reports involve female patients and 21.7% involve male patients. The largest age group is adult at 77%. These figures reflect who reports side effects, not underlying risk.

Sex

Female73.1%
Male21.7%
Unknown5.1%

Age group

< 20.9%
2–110.0%
12–170.5%
18–6477.5%
65+21.1%

What is methyltestosterone used for

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

AnaemiaAndrogen Replacement TherapyApathyAstheniaBack PainBlood Creatinine IncreasedBlood GlucoseBlood Testosterone DecreasedBlood Testosterone IncreasedBlood Pressure MeasurementDrug AbuseDrug Use For Unknown IndicationErectile DysfunctionFatigueFoetal Exposure During Pregnancy

Showing 15 of 47 indications

Methyltestosterone brand names and reporting trend

Methyltestosterone is sold under the brand name Virilon.

Brand names

Virilon347

Quarterly reports (20042025)

20052010201520202025

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

Taking methyltestosterone with another medication?

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