Anisindione
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Drug reference
Testosterone
Androgen / anabolic steroid (sex hormone) · Hormone replacement therapy; Hypogonadism treatment
Also known as Testosterone enanthate, Testosterone cypionate, Testosterone propionate, Testosterone undecanoate, Androgen
START
Confirm low AM testosterone ×2 + symptoms; e.g. gel 40.5–81 mg/day or enanthate 75–100 mg IM weekly equivalent; titrate to mid-normal trough
TYPICAL MAX
Regimen-specific; titrate to mid-normal levels (avoid supraphysiologic)
STOP IF
Haematocrit >54%, new prostate cancer, VTE/MACE, severe BPH symptoms
WATCH
Haematocrit, PSA + DRE (baseline & periodic), testosterone level, lipids/BP, mood
CDSCO approvedSchedule HATC G03BA03
KDIGO 2024 + manufacturer label
- ONSET
- 1d · early effect (depot)
- PEAK
- 3d · depot ester peak (regimen-dependent)
- t½
- 1w · depot effective t½ (illustrative)
- DURATION
- 2w · 2-week dosing interval (ester)
EXCRETION
Hepatic metabolism; ~90% renal conjugates
route + CYP
INTERACTIONS
10 major
SEVERE in our sources
PREGNANCY
Contraindicated — virilisation of a female fetus
FDA category + note
Top interactionssee all 12 →
- AnisindioneSevereDatabaseDDInter
- CarfilzomibSevereDatabaseDDInter
- DicoumarolSevereDatabaseDDInter
- LeflunomideSevereDatabaseDDInter
Available in India
47 branded formulations and 3 fixed-dose combinations. Look up specific brands in the Drugs workspace.
Mechanism
Endogenous androgen; binds androgen receptors to drive male sexual differentiation, secondary sexual characteristics, libido, erythropoiesis, bone and muscle anabolism; aromatised to oestradiol and 5α-reduced to dihydrotestosterone.
Indications
Male hypogonadism (primary or hypogonadotropic) — replacementDelayed male puberty (selected)Certain hormone-receptor settings (specialist)
Dosing
- Adult
- Depends on ester/route: e.g. testosterone enanthate/cypionate 50–400 mg IM every 2–4 weeks; undecanoate 1000 mg IM at 0, 6 weeks then q10–14 weeks; transdermal gel 40.5–81 mg/day; titrate to mid-normal trough levels.
- Pediatric
- Delayed puberty: low-dose short-course esters (specialist endocrinology).
- Renal adjustment
- No specific adjustment; caution with fluid retention.
- Hepatic adjustment
- Avoid oral 17-alpha-alkylated forms in hepatic disease; caution with others.
- Geriatric
- Higher CV/prostate/polycythaemia risk; individualise, monitor.
- Max dose
- Regimen-specific (e.g. undecanoate 1000 mg/injection; gel ~100 mg/day) — titrate to levels
Pharmacokinetics
Onset
Days–weeks (depot)
Peak effect
Ester/route-dependent
Duration
Days (gel) to weeks–months (depot esters)
Half-life
Free testosterone short; depot esters effective t½ days–weeks
Bioavailability
Oral testosterone poor (first-pass); IM/transdermal effective
Protein binding
~98% (SHBG/albumin)
Metabolism
Hepatic; aromatisation and 5α-reduction
Excretion
Renal (~90% as conjugated metabolites); faecal
Contraindications
- Known/suspected prostate or male breast carcinoma
- Pregnancy (virilisation of fetus)
- Severe untreated polycythaemia
- Severe cardiac/hepatic/renal disease (relative)
Side effects
Common
Acne, oily skinErythrocytosis/raised haematocritFluid retentionGynaecomastiaInjection-site reaction; application-site reaction (gel)
Serious
- Polycythaemia → thrombosis
- Worsening BPH/urinary obstruction; prostate cancer progression
- Possible increased major adverse cardiovascular events
- Hepatic toxicity (oral alkylated forms)
- Venous thromboembolism
- Secondary infertility (spermatogenesis suppression)
Pregnancy & lactation
Pregnancy
Contraindicated — virilisation of a female fetus
Lactation
Contraindicated/avoid; gel transfer risk to others
Drug interactions
Carfilzomib
Severe
Database
Drug interaction classified as: synergy
Source: DDInter
Dicoumarol
Severe
Database
Clinical effect not specified
Source: DDInter
Leflunomide
Severe
Database
Clinical effect not specified
Source: DDInter
Lomitapide
Severe
Database
Clinical effect not specified
Source: DDInter
Mipomersen
Severe
Database
Clinical effect not specified
Source: DDInter
Pazopanib
Severe
Database
Clinical effect not specified
Source: DDInter
Pexidartinib
Severe
Database
Clinical effect not specified
Source: DDInter
Teriflunomide
Severe
Database
Clinical effect not specified
Source: DDInter
Warfarin
Severe
Database
Enhanced anticoagulant effect → raised INR/bleeding
Monitor INR closely, adjust warfarin
Source: Kimi deep-research + Cla
Dutasteride
Moderate
Database
Opposing hormonal effect; confounds therapy
Avoid concurrent unless clinically justified
Source: Kimi deep-research + Cla
Corticosteroids
Moderate
Database
Additive fluid retention/oedema
Monitor oedema, BP
Source: Kimi deep-research + Cla
Related guidelines
Ask House about Testosterone
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: KD Tripathi 7e, Goodman & Gilman 14e, Katzung, BNF·Verified: 2026-05-19 · House clinical team·Cockpit curated: 2026-05-19