Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ANDROID 25 vs CEPHULAC
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, a synthetic disaccharide, is not absorbed from the gastrointestinal tract. It is metabolized by colonic bacteria to form short-chain fatty acids (e.g., lactic, acetic, formic acids), which acidify the colonic contents. In hepatic encephalopathy, the acidic environment converts ammonia (NH3) to ammonium (NH4+), which is poorly absorbed and excreted in feces. Additionally, the osmotic effect of lactulose draws water into the colon, softening stools and increasing bowel movements.
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) including the prevention and treatment of coma
Testosterone 25 mg subcutaneously or intramuscularly every 2 to 4 weeks. Alternatively, 125 mg intramuscularly every 10 days.
30-45 m L (6.67-10 g lactulose) orally 3-4 times daily for constipation; for hepatic encephalopathy, 30-45 m L orally 3-4 times daily titrated to produce 2-3 soft stools per day, or 300 m L in 700 m L of water or saline as retention enema for 30-60 min every 4-6 hours.
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 is 7-10 hours (renal impairment: prolonged); systemic absorption is minimal (<3%) after oral administration, so half-life reflects clearance of absorbed fraction.
Primarily hepatic via reduction and oxidation; metabolites include androsterone and etiocholanolone; excreted in urine.
Not absorbed; metabolized by colonic bacteria (e.g., Lactobacillus, Bacteroides) to low molecular weight organic acids.
Renal: 90% (as glucuronide and sulfate conjugates, 5–10% unchanged); fecal/biliary: 10%
Primarily renal (20-30% as unchanged drug) and fecal (up to 70% as unmetabolized drug via biliary elimination; following gastric acid-mediated degradation, only 5-10% reaches urine as intact lactulose; hepatic metabolism is negligible).
97–99% (sex hormone-binding globulin and albumin)
Negligible (<5%): lactulose does not bind significantly to albumin or other plasma proteins due to its hydrophilic nature.
0.3–0.6 L/kg; indicates distribution into lean muscle and sex organs
0.5-1.0 L/kg (estimated from systemic absorption studies; limited data due to minimal absorption; reflects distribution largely into extracellular water).
Oral: <5% (methyltestosterone: ~20–25% due to 17α-alkylation); IM: 100%
Oral: <3% (due to poor absorption and extensive metabolism by colonic bacteria; most of the drug remains in the gut lumen). Rectal: similar to oral, as systemic absorption is minimal.
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 as lactulose is minimally absorbed and primarily acts locally in the colon.
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.
Not specifically adjusted based on Child-Pugh score; dose is titrated to achieve desired stool frequency; caution in severe hepatic impairment due to risk of electrolyte disturbances.
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: 2.5-10 m L/day in divided doses; older children: 10-25 m L/day; adolescents: 15-30 m L/day; all for constipation; for hepatic encephalopathy, doses as low as 5-10 m L 3-4 times daily with dose adjusted to produce 2-3 soft stools per day.
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.
Initiate at lower end of dosing range (15-30 m L/day) due to increased risk of dehydration and electrolyte imbalance; monitor for diarrhea and adjust accordingly.
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 imbalance with prolonged use, especially in debilitated patients,Diarrhea may cause fluid and electrolyte loss,Galactose intolerance (contraindicated in patients requiring low galactose diet due to lactose content in some preparations),Monitor serum electrolytes in patients receiving high doses for hepatic encephalopathy
Known or suspected prostate cancer; male breast cancer; pregnancy; lactation; hypersensitivity to methyltestosterone; severe hepatic impairment.
Patients requiring a low-galactose diet (lactulose contains galactose and lactose),Intestinal obstruction,Suspected gastrointestinal obstruction or perforation
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. Avoid concurrent use with other laxatives unless directed. High-fiber foods may enhance effect; ensure adequate fluid intake.
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 (CEPHULAC) is not absorbed systemically; therefore, fetal exposure is negligible. Animal studies have not shown teratogenic effects. In clinical practice, no fetal risks have been identified in any trimester.
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 excreted into breast milk due to minimal systemic absorption. It is considered compatible with breastfeeding. M/P ratio: Not applicable (negligible 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. Pharmacokinetics are unchanged in pregnancy due to lack of systemic absorption. Standard dosing of 15-30 m L (10-20 g) once daily, up to 60 m L/day in divided doses, is appropriate.
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.
Cephulac (lactulose) is a non-absorbable disaccharide used for constipation and hepatic encephalopathy. In hepatic encephalopathy, titrate to produce 2-3 soft stools per day. Monitor serum electrolytes, especially in elderly or renal impairment. Onset of action for constipation may be 24-48 hours. Do not confuse with other lactose-containing products.
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.
Take exactly as prescribed; may take 24-48 hours to produce a bowel movement.,For hepatic encephalopathy, maintain 2-3 soft stools daily; do not skip doses.,May cause bloating, gas, or cramping initially; usually resolves.,Do not take other laxatives without consulting your doctor.,Report severe diarrhea, vomiting, or muscle cramps to your healthcare provider.
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 CEPHULAC, 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.. CEPHULAC is a Laxative that works by Lactulose, a synthetic disaccharide, is not absorbed from the gastrointestinal tract. It is metabolized by colonic bacteria to form short-chain fatty acids (e.g., lactic, acetic, formic acids), which acidify the colonic contents. In hepatic encephalopathy, the acidic environment converts ammonia (NH3) to ammonium (NH4+), which is poorly absorbed and excreted in feces. Additionally, the osmotic effect of lactulose draws water into the colon, softening stools and increasing bowel movements.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ANDROID 25 and CEPHULAC 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 CEPHULAC is: 30-45 m L (6.67-10 g lactulose) orally 3-4 times daily for constipation; for hepatic encephalopathy, 30-45 m L orally 3-4 times daily titrated to produce 2-3 soft stools per day, or 300 m L in 700 m L of water or saline as retention enema for 30-60 min every 4-6 hours.. 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 CEPHULAC 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. CEPHULAC is classified as Category C. Lactulose (CEPHULAC) is not absorbed systemically; therefore, fetal exposure is negligible. Animal studies have not shown teratogenic effects. In clinical practice, no fetal risks . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.