Is venlafaxine (Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)) a controlled substance and does it require follow-up with a healthcare provider before ordering a refill?

Venlafaxine Controlled Substance Status and Refill Requirements

Venlafaxine is NOT a controlled substance and does not require DEA authorization or special prescribing restrictions, but it does require regular clinical follow-up to monitor for blood pressure elevation, cardiac effects, and safe discontinuation. 1

Controlled Substance Classification

• Venlafaxine is explicitly not classified as a controlled substance according to FDA labeling, with in vitro studies showing virtually no affinity for opiate, benzodiazepine, phencyclidine (PCP), or NMDA receptors. 1

• The drug showed no significant CNS stimulant activity in rodents and demonstrated no significant stimulant or depressant abuse liability in primate drug discrimination studies. 1

• While clinical trials revealed no indication of drug-seeking behavior, the FDA notes that physicians should carefully evaluate patients with a history of drug abuse and monitor for signs of misuse, as isolated case reports exist of dependence in patients with prior substance abuse history. 1, 2

Required Clinical Monitoring Before Refills

Blood pressure and pulse monitoring is essential before ordering refills, as venlafaxine causes dose-dependent blood pressure elevation that may require treatment discontinuation. 3, 4, 5

Specific Monitoring Parameters:

• Cardiovascular assessment: Check blood pressure and pulse at each visit, particularly when initiating treatment or adjusting dosage, as cardiac conduction abnormalities have been reported in a small number of patients. 3, 4

• For patients over 40 years: Consider screening electrocardiogram before initiation if cardiac risk factors are present, as venlafaxine should be prescribed with caution in patients with cardiac disease. 3, 4

• Dose-dependent effects: Higher doses (150-225 mg/day) require 2-4 weeks for titration and carry increased risk of blood pressure increases. 3

Clinical Pitfalls to Avoid:

• Do not abruptly discontinue: Venlafaxine must be tapered when treatment is being discontinued because a withdrawal syndrome has been well-described, making follow-up essential for safe discontinuation planning. 3

• Drug interaction monitoring: For patients on tamoxifen, venlafaxine has minimal effects on tamoxifen metabolism (unlike certain SSRIs like paroxetine), making it a preferred option for managing hot flashes in breast cancer survivors. 3

• Overdose risk awareness: Venlafaxine overdoses are more frequently fatal than SSRI overdoses, and the drug carries risk of QT interval prolongation, reinforcing the need for regular clinical oversight. 5

Practical Refill Protocol

You can order refills without provider contact IF:

• Blood pressure remains stable and within normal limits 4
• Patient is tolerating current dose without new cardiovascular symptoms 3
• No planned dose changes or discontinuation 3

You MUST contact the provider before refilling IF:

• Blood pressure is elevated or trending upward 3, 4
• Patient reports new cardiac symptoms or palpitations 3
• Patient wants to stop the medication (requires taper plan) 3
• Patient has history of substance abuse (requires closer monitoring) 1