Prescription drug Published: RCT evidence Established use

Guanfacine: dosing, timing and what to expect

An alpha-2 agonist used for ADHD (often alongside a stimulant) and blood pressure. Calming rather than stimulating — the other direction from everything else in the ADHD toolbox.

Also known as Intuniv, Tenex

Educational research reference Prescription Medications

Quick reference. Everything you need to run Guanfacine — dosing, frequency, reconstitution math for the vial sizes people actually buy, and what it stacks with. For anything specific to your situation, ask the Guru.

Guanfacine quick start

Route: Oral
Typical dose: Physician-set — commonly 1–4 mg/day (ER)
Frequency: Daily
Half-life: ~17 hours.
Cycle: Continuous under physician supervision.

These are the numbers people actually run, drawn from the published record and from what the community has settled on over time. Educational reference, not medical advice — a starting point to work from, and one you can adjust as you learn how you respond.

How to run it

How often: Daily
Cycle length: Continuous under physician supervision.
Half-life: ~17 hours.
Route: Oral

Consistency matters more than perfect timing. Pick a slot in your day you will actually keep, and let DoseIQ handle the rest.

What to expect

Most people tolerate Guanfacine well. Here is what is worth knowing going in, so nothing catches you by surprise.

Lowers blood pressure and sedates — additive with every other BP-lowering and sedating thing in the stack. Never stopped abruptly (rebound hypertension).

Known interactions

Interactions involving Guanfacine's drug class that DoseIQ screens for. Each one cites where it comes from — an FDA label section or the published record — because an interaction warning you can't trace is just noise.

Worth knowing PDE5 + blood-pressure medication — additive lowering

Usually fine and often co-prescribed, but stacked vasodilation can show up as lightheadedness.

What to do: Rise slowly; mention dizziness to your prescriber.

Source: FDA labels, sildenafil/tadalafil §7

Worth knowing Multiple sedating agents — additive drowsiness

Trazodone, gabapentin, micronized progesterone — each mild alone, cumulative together.

What to do: Time them all at night, and judge morning grogginess honestly.

Source: Class pharmacology

DoseIQ screens your whole protocol against these rules automatically — every compound, prescription and supplement you track, cross-checked as you add them. Serious flags are always free.

Preparing it

Guanfacine does not need reconstituting — it comes ready to use.

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This page is an educational research reference and is not medical advice. Dose figures reflect the published record and what the community has converged on — starting points to weigh, not instructions. Consult a qualified healthcare provider before starting any protocol.