Selank vs DSIP: Daytime Calm vs Night-Time Sleep, Evidence, FDA Status, Dosing and Cost

Every figure is an all-in monthly price covering the medication, physician review, refill management and shipping. There is no separate membership fee, and Pepti is cash-pay and does not bill insurance. Current pricing always lives on each product page.

Day versus night, and a shared thread

The simplest way to separate them is timing. Selank is aimed at the daytime experience of anxiety; DSIP at the night. What is interesting is that both are described as working partly through the body's own enkephalins: Selank by slowing their breakdown, DSIP by triggering their release. That is animal and laboratory work, but it helps explain why prescribers often see them as two halves of one stress-and-sleep picture rather than rivals.

Which problem comes first

The honest question to ask yourself is whether you sleep badly because your mind will not settle, or whether sleep itself is the problem. Selank's own page notes that where poor sleep is downstream of a racing mind, some physicians start with Selank; where sleep is the primary complaint, DSIP is the more direct conversation. Selank is not a sleeping aid: in the 2015 trial, longer sleep was one of the benzodiazepine side effects that adding Selank reduced.

SERENITY puts both in one vial with two growth-hormone-axis peptides:

Note the timing: in SERENITY the Selank is taken at bedtime with the DSIP, not during the day. The proportions are fixed, and no study has tested this combination. It suits people describing stress and sleep together, and whose physician thinks the growth-hormone components are worth including.

Both were placed in Category 2 in 2023 and both are out of it, but their paths since then differ. As of the FDA pages checked in September 2026:

Neither is banned, and both remain legal to prescribe and dispense as compounded medications. DSIP was the only one of the seven peptides reviewed that week not to receive a favorable vote. Compounded medications are not FDA approved, and neither is an FDA-approved drug. See are peptides FDA approved.

Both are injected under the skin into the abdomen or thigh, rotating sites, five days a week with weekends off. Both vials are multi-dose solutions shipped ready to use, refrigerated with ice packs, with sterile syringes and alcohol prep pads.

The draw is the same 25 units, but the strengths differ, so Selank delivers twice the milligrams per dose. On a U-100 insulin syringe, 1 unit is 0.01 mL, and the milligram figures are arithmetic for reading a label, not a way to set a dose. Your physician sets your directions after reviewing your intake, and your directions are printed on the vial. Neither weekday schedule comes from the trials, which used nasal Selank and intravenous DSIP. Refills run every 28 days, one vial per fill. More is in Selank dosage and DSIP dosage.

Selank. The Russian trials, using a formal side-effect scale, reported no sedation, memory impairment, dependence or withdrawal. With the injection, mostly injection-site redness, mild soreness or bruising. Some people describe early fatigue or a flat feeling, and a few feel wired; both usually settle. It has not been studied with SSRIs, SNRIs, stimulants or antipsychotics. More is in Selank side effects.

DSIP. The small intravenous insomnia studies reported it as well tolerated. A withdrawal series reported transient headache, nausea and vertigo in a handful of patients. Prescribers today mostly report injection-site reactions, with occasional early headache or vivid dreams. Tell your physician about any opioid, benzodiazepine, sedative or regular alcohol use, because its described mechanism runs through the body's opioid system, and about every medication, because laboratory work reports DSIP being broken down by an enzyme some blood-pressure medicines inhibit. More is in DSIP side effects.

For both, message your care team about anything unexpected, and about any marked change in mood. Facial or throat swelling, a widespread rash or difficulty breathing is an emergency: call 911 first, then tell your physician.

Both have more human data than many compounded peptides, and both have clear limits. Selank's anxiety trials are small, Russian, nasal, compared with benzodiazepines rather than placebo, and unreplicated elsewhere. DSIP's insomnia trials are small, decades old and intravenous, and the independent ones concluded the effect was too weak to be clinically meaningful; the controlled studies that measured slow-wave sleep did not find it increased. Neither has a trial of the injection. Any provider calling either a reliable fix for anxiety or insomnia is overstating it.

Neither can be bought legitimately without a prescription. Sites selling them "for research use only" are not accountable for what is in the vial: identity, purity, sterility and concentration are untested. The prescription route:

1. Complete a free online intake covering your history, medications and what you want help with.
2. A physician licensed in your state reviews it, usually within 24 hours.
3. If it is appropriate, a PCAB-accredited, FDA-registered US 503A compounding pharmacy prepares it to that prescription. Lot test results are published at /quality/lab-results.
4. It ships refrigerated with ice packs and your directions printed on the vial.
5. Your physician stays reachable for questions and dose changes.

Pepti prescribes both in every state except Oklahoma, plus DC Step by step: how to get Selank prescribed online and how to get DSIP prescribed online. Related: peptides for sleep and peptides for anxiety and mood.