Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ANDROID 25 vs CHRONULAC
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Android 25 contains methyltestosterone, a synthetic androgen that binds to androgen receptors, promoting protein synthesis and anabolic effects. It also inhibits gonadotropin secretion from the pituitary, reducing endogenous testosterone production.
Lactulose is a synthetic disaccharide that is not absorbed in the small intestine. It is hydrolyzed by colonic bacteria to form low molecular weight acids (mainly lactic and acetic acid), which osmotically draw water into the colon, softening stools and increasing stool frequency. Additionally, lactulose decreases colonic p H, which traps ammonia (NH3) as ammonium (NH4+), reducing serum ammonia levels.
Hypogonadism in males (primary and secondary),Delayed puberty in males,Metastatic breast cancer in women (as palliative therapy)
Treatment of constipation,Hepatic encephalopathy (portal-systemic encephalopathy)
Testosterone 25 mg subcutaneously or intramuscularly every 2 to 4 weeks. Alternatively, 125 mg intramuscularly every 10 days.
10-30 m L orally once daily to twice daily; for acute constipation, 20-30 m L initially; for hepatic encephalopathy, 30-60 m L every 1-2 hours to achieve 2-3 soft stools daily.
Terminal elimination half-life: 10–100 minutes (testosterone); clinical context: rapid clearance necessitates frequent dosing or use of esters for sustained effect
Terminal elimination half-life approximately 1.5-2.5 hours in adults with normal renal function; may be prolonged to 4-8 hours in patients with renal impairment.
Primarily hepatic via reduction and oxidation; metabolites include androsterone and etiocholanolone; excreted in urine.
Not absorbed systemically; metabolized by colonic bacteria (e.g., Lactobacillus, Bacteroides) to lactic acid, acetic acid, and other short-chain fatty acids.
Renal: 90% (as glucuronide and sulfate conjugates, 5–10% unchanged); fecal/biliary: 10%
Primarily renal (as unchanged drug and metabolites): ~40-50% of dose excreted in urine within 24 hours; biliary/fecal elimination accounts for the remainder, with approximately 2-5% recovered in feces as parent compound.
97–99% (sex hormone-binding globulin and albumin)
Negligible (<5%), primarily to albumin.
0.3–0.6 L/kg; indicates distribution into lean muscle and sex organs
Approximately 0.25 L/kg; distributes mainly into extracellular fluid.
Oral: <5% (methyltestosterone: ~20–25% due to 17α-alkylation); IM: 100%
Oral: poorly absorbed; <3% reaches systemic circulation as intact lactulose; the remainder is metabolized by colonic bacteria.
No dose adjustment required for GFR ≥30 m L/min. For GFR <30 m L/min, consider reducing dose or increasing interval; monitor for fluid retention and hypertension.
No dose adjustment required for renal impairment; caution in severe renal impairment due to electrolyte disturbances.
Contraindicated in Child-Pugh class B or C cirrhosis. For mild hepatic impairment (Child-Pugh A), start with lower dose (e.g., 12.5 mg every 2 weeks) and titrate based on response and liver function.
No adjustment needed; used in hepatic encephalopathy at higher doses.
Not recommended for use in pediatric patients (safety and efficacy not established). For male adolescents with hypogonadism, individualize: start at 12.5 mg every 2 weeks and adjust based on testosterone levels and growth.
Infants: 2.5-5 m L orally once daily; Children 1-5 years: 5-10 m L once daily; Children 6-12 years: 10-15 m L once daily; Adolescents: 15-30 m L once daily; adjust based on response.
Start with lower initial dose (e.g., 12.5 mg every 2 weeks); monitor prostate-specific antigen (PSA) and hematocrit frequently. Avoid in patients with prostate cancer or untreated sleep apnea.
Start at low end of dosing range (10-15 m L once daily) due to increased risk of electrolyte imbalance and dehydration; monitor fluid/electrolyte status.
WARNING: Androgens are contraindicated in pregnancy due to masculinization of female fetus. Hepatotoxicity, including peliosis hepatis and hepatic neoplasms, has been reported with prolonged use.
None.
Use with caution in patients with hepatic, renal, or cardiovascular disease; may cause gynecomastia, edema, hypercalcemia, and polycythemia; monitor liver function, lipid profile, and hematocrit periodically; may accelerate bone maturation in children; risk of prostate hypertrophy and urethral obstruction.
Electrolyte disturbances (e.g., hypernatremia, hypokalemia) with prolonged use or high doses,Diarrhea may cause fluid and electrolyte loss,Risk of colonic distention or fecal impaction,Use caution in patients with galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption (contains galactose and lactose)
Known or suspected prostate cancer; male breast cancer; pregnancy; lactation; hypersensitivity to methyltestosterone; severe hepatic impairment.
Patients with galactosemia,Intestinal obstruction,Known hypersensitivity to lactulose
Take with food containing fat (e.g., avocado, nuts, olive oil) to enhance absorption. Avoid grapefruit juice as it may increase testosterone levels via CYP3A4 inhibition. Limit alcohol due to potential liver effects.
No specific food interactions, but avoid concurrent use with other laxatives. Ensure adequate fluid intake to reduce risk of hypernatremia.
Android 25 (methyltestosterone) is an androgen. First trimester: Virilization of female fetus, including clitoromegaly, labial fusion, urogenital sinus abnormalities if exposure occurs before 12 weeks gestation. Second and third trimesters: Continued risk of female pseudohermaphroditism, and potential for masculinization of female external genitalia. Androgens can cross the placenta and may also cause skeletal abnormalities and growth retardation. Pregnancy category X.
Lactulose (CHRONULAC) is not absorbed systemically; no teratogenic effects are expected. No adequate and well-controlled studies in pregnant women; animal reproduction studies not conducted. Based on lack of systemic absorption, risk to fetus is low across all trimesters.
Methyltestosterone is excreted into breast milk; M/P ratio not established. May cause virilization in female infants and premature sexual development in male infants. Androgens can suppress lactation. Use during breastfeeding is contraindicated.
Lactulose is not absorbed orally; therefore, excretion into breast milk is negligible. Considered compatible with breastfeeding; no M/P ratio available due to lack of systemic absorption.
Android 25 is contraindicated in pregnancy, so no dosing adjustments are applicable. If used inadvertently, discontinue immediately. No pharmacokinetic data to guide dose changes; avoid use entirely.
No dose adjustment required during pregnancy. Pharmacokinetics of lactulose are unchanged due to lack of systemic absorption. Use standard dosing for constipation (15-30 m L daily, titrated to effect).
Android 25 (testosterone undecanoate) requires absorption via lymphatic system; administer with fat-containing meal. Monitor serum testosterone levels 3-5 hours post-dose. Avoid in patients with breast cancer or known or suspected prostate cancer. Risk of polycythemia; check hematocrit before and during therapy.
Chronulac (lactulose) is a non-absorbable disaccharide used for constipation and hepatic encephalopathy. Onset of action for constipation is 24-48 hours; monitor for electrolyte disturbances (hypernatremia) with prolonged use. Do not use with other laxatives in acute abdomen. For hepatic encephalopathy, titrate to 2-3 soft stools daily.
Take capsules with meals, especially those containing fat, to improve absorption.,Do not chew or crush capsules; swallow whole.,Report signs of deep vein thrombosis (leg swelling, pain) or pulmonary embolism (sudden dyspnea, chest pain).,Women of reproductive potential should avoid pregnancy; use effective contraception.,Keep out of reach of children; testosterone can cause serious harm if accidentally ingested.,Regular blood tests (testosterone, hematocrit, PSA, lipid profile) are required.
May take 24-48 hours to produce a bowel movement; do not use if you have abdominal pain, nausea, or vomiting.,Mix with fruit juice, milk, or water to improve taste.,Store at room temperature; do not freeze.,Report excessive diarrhea or electrolyte imbalance symptoms (muscle cramps, weakness).
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ANDROID 25 vs CHRONULAC, answered by our medical review team.
ANDROID 25 is a Androgen that works by Android 25 contains methyltestosterone, a synthetic androgen that binds to androgen receptors, promoting protein synthesis and anabolic effects. It also inhibits gonadotropin secretion from the pituitary, reducing endogenous testosterone production.. CHRONULAC is a Osmotic Laxative that works by Lactulose is a synthetic disaccharide that is not absorbed in the small intestine. It is hydrolyzed by colonic bacteria to form low molecular weight acids (mainly lactic and acetic acid), which osmotically draw water into the colon, softening stools and increasing stool frequency. Additionally, lactulose decreases colonic p H, which traps ammonia (NH3) as ammonium (NH4+), reducing serum ammonia levels.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ANDROID 25 and CHRONULAC depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ANDROID 25 is: Testosterone 25 mg subcutaneously or intramuscularly every 2 to 4 weeks. Alternatively, 125 mg intramuscularly every 10 days.. The standard adult dose of CHRONULAC is: 10-30 m L orally once daily to twice daily; for acute constipation, 20-30 m L initially; for hepatic encephalopathy, 30-60 m L every 1-2 hours to achieve 2-3 soft stools daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ANDROID 25 and CHRONULAC in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ANDROID 25 is classified as Category C. Android 25 (methyltestosterone) is an androgen. First trimester: Virilization of female fetus, including clitoromegaly, labial fusion, urogenital sinus abnormalities if exposure oc. CHRONULAC is classified as Category C. Lactulose (CHRONULAC) is not absorbed systemically; no teratogenic effects are expected. No adequate and well-controlled studies in pregnant women; animal reproduction studies not . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.