Short answer: The Serostim label starts at 0.1 mg/kg under the skin once daily at bedtime, up to 6 mg. By weight that is 6 mg above 55 kg, 5 mg at 45 to 55 kg, 4 mg at 35 to 45 kg and 0.1 mg/kg below 35 kg. A start of 0.1 mg/kg every other day is considered for people at higher risk of side effects, such as glucose intolerance.
This is what the FDA label says. Follow your prescriber. Your prescriber may use a different dose or pace than the label's standard schedule.
What Serostim is approved for: Serostim is approved for adults with HIV and wasting or cachexia, to increase lean body mass and body weight and improve physical endurance. The label says antiretroviral therapy must be taken at the same time (section 1). It is not approved for growth hormone deficiency or for HIV lipodystrophy.
Source
SEROSTIM (somatropin) for injection, for subcutaneous use, prescribing information. EMD Serono. DailyMed, version published September 25, 2026. DailyMed setid 62b01d29-90f0-45b2-a0c4-3a750ba36c8a
Serostim is a powder in a 4 mg, 5 mg or 6 mg vial, mixed with 0.5 mL to 1 mL of the diluent that comes with it and injected under the skin with a standard sterile syringe and needle (sections 2.2 and 3).
The 5 mg and 6 mg vials are mixed with Sterile Water for Injection and used right away, one dose per vial. The 4 mg vial is mixed with Bacteriostatic Water containing benzyl alcohol and can be refrigerated for up to 14 days (sections 2.2 and 16.2).
The diluent is aimed at the vial wall and the vial is swirled, not shaken. The solution is used only if clear or slightly opalescent. Sites on the thigh, upper arm, abdomen or buttock are rotated (section 2.2).
The table below is the label's schedule, from the Dosage and Administration section. Numbers are copied exactly; the section is in brackets.
| Weight Range | Dose |
|---|---|
| >55 kg (>121 lb) | 6 mg subcutaneously once daily |
| 45-55 kg (99-121 lb) | 5 mg subcutaneously once daily |
| 35-45 kg (75-99 lb) | 4 mg subcutaneously once daily |
| <35 kg (<75 lb) | 0.1 mg/kg subcutaneously once daily |
The label says the doses are based on an approximate daily dosage of 0.1 mg/kg, given once daily at bedtime.
A starting dose of 0.1 mg/kg every other day should be considered for people at increased risk of growth hormone side effects, such as glucose intolerance. In the trial it caused fewer side effects and a similar improvement in work output compared with daily dosing.
For side effects that may be related to growth hormone, dose reductions are considered, either a lower total daily dose or fewer doses per week.
Most of the effect on work output and lean body mass appeared by 12 weeks and held over another 12 weeks. There are no controlled data on continuous use beyond 48 weeks, and none on intermittent use.
Treatment is carried out under the regular guidance of a physician experienced in diagnosing and managing HIV infection.
Older people may be more sensitive to somatropin, and a lower starting dose and smaller increases should be considered.
People with diabetes may need their insulin or other diabetes medicine doses adjusted.
Unmixed cartons are stored at room temperature, 15 to 30 C (59 to 86 F). Mixed 4 mg vials are refrigerated at 2 to 8 C for up to 14 days and not frozen.
The Serostim label gives no missed-dose instruction. Ask your prescriber or pharmacist what to do if a dose is missed.
In Dose Track you set up Serostim as a protocol with the dose and schedule your prescriber gave you. A protocol can hold dose steps, each with its own dose and length in days or weeks, so a step-up plan like the one on the label can be entered once and the app moves to the next step on its own. Reminders follow the schedule, and every dose is logged with the date and time, so you can see which step you are on and when your last dose was. The app follows what you enter; it does not choose or change a dose.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.