SD Medical Cannabis Dose & Supply — 3 oz / 14-Day Rolling Cap

Last verified: May 2026

The 3 oz / 14-Day Rolling Window

The core SD patient limit, codified at SDCL § 34-20G-71 and SDDOH rules, is 3 ounces of cannabis flower (or product equivalent) per 14-day rolling period. The rolling window is calculated at the point of sale by the Metrc seed-to-sale software:

• Each purchase is added to the patient’s 14-day rolling total.
• As days elapse, older purchases drop out of the rolling window.
• Patients can purchase smaller increments throughout the 14-day window as long as the rolling total stays at or below 3 oz.

Possession Limit — Also 3 oz

Patients may possess up to 3 oz of marijuana flower at any time, plus DOH-set quantities of cannabis-infused products. The possession limit and the 14-day-rolling-purchase limit are both 3 oz, which means in practice that patients exhausting their purchase ceiling on day 1 should not retain product beyond the 14-day cycle.

Product Equivalents

The 3 oz flower limit translates to product-equivalent quantities for non-flower forms. SDDOH establishes equivalency factors for:

• Edibles — in milligrams of THC.
• Tinctures and oral oils — in milligrams of THC.
• Vape cartridges — by gram of cannabis input.
• Concentrates — by gram of concentrate.

The equivalency factors are managed within Metrc; dispensary point-of-sale systems automatically calculate the equivalent ounce-of-flower units when a patient purchases non-flower products.

Home Cultivation — Conditional, Up to 3 Plants

Registered patients may apply to grow up to three plants at their primary residence. Cultivation typically requires either:

• Practitioner authorization for additional plants beyond the default, OR
• Residence in an area without ready dispensary access (variously cited as 50 or 75 miles from nearest dispensary; verify current rule with SDDOH directly).

The frequently cited "no dispensary within X miles" rule derives from administrative rule and patient-cultivation permit guidance rather than statute, and the radius has shifted as the dispensary network has expanded. Patients planning to cultivate should verify the current radius rule directly with the Department of Health.

The home-cultivation add-on fee is $20 per year beyond the standard $75 patient registration. There is no recreational home cultivation in South Dakota — adult-use cultivation outside the medical program faces SDCL § 22-42-6 felony liability.

Minor-Patient Purchase Restrictions

Minor patients (under 18) may not purchase inhalable cannabis products in South Dakota. The restriction applies to flower, vape cartridges, pre-rolls, and concentrates intended for inhalation. Minor patients are typically restricted to oral preparations (tinctures, edibles), oral oils, and topicals.

Dose Recommendations and Practitioner Discretion

Unlike some state programs that impose a strict daily-mg-of-THC ceiling (Alabama’s 50 mg/75 mg cap, for instance), SD does not statutorily cap daily THC intake. Practitioners exercise clinical discretion to recommend starting dose and titration regimen. The 3 oz / 14-day cap creates an effective daily-consumption ceiling but does not prescribe per-dose limits.

Drug-Drug Interaction Considerations

Patients should be aware of cannabis pharmacokinetic interactions, particularly:

• CYP3A4 inducers and inhibitors. Many cannabinoids are CYP3A4 substrates.
• Warfarin. CBD is a CYP2C9 inhibitor that may dramatically alter INRs.
• Sedative-hypnotic medications. Cannabis may potentiate CNS depression with benzodiazepines, opiates, and other sedatives.
• Antihypertensives. Cannabis may produce orthostatic hypotension; combining with antihypertensives may produce additive effects.

Pregnant and lactating patients should avoid cannabis. Patients with mental-health histories (psychosis, severe depression, suicidality) should be screened carefully — cannabis use can exacerbate certain psychiatric conditions.

Tax Layer at the Register

Compassion-Act-equivalent purchases are subject to:

• 4.5% state sales tax on retail medical cannabis sales.
• Up to 2% local sales tax depending on jurisdiction.
• No separate cannabis-specific excise tax.

Total out-the-door tax burden is approximately 4.5%–6.5%, among the lowest medical-cannabis tax structures of any U.S. program. See taxation page.

Insurance Non-Coverage

Health insurance does not cover SD medical cannabis. Federal Schedule I status (despite April 2026 Schedule III rescheduling) prevents Medicare, Medicaid, Tricare, VA, and private commercial insurers from covering cannabis as a medication. Patients pay 100% out-of-pocket.

Practical Notes

• Track your 14-day rolling window. Metrc tracks it for you, but plan purchases relative to your consumption pattern.
• Bring cash or debit. Credit cards are not accepted.
• Home cultivation is restrictive. Verify current radius rules with SDDOH before assuming you qualify.
• Do not pool with another patient or caregiver. Each patient’s allotment is individually tracked.

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