Papaverina Cloridrato Monico (Papaverine Hydrochloride)

Papaverine hydrochloride is used in clinical settings that require relaxation of smooth muscle tone, particularly within the vascular and gastrointestinal systems.

• Coronary artery spasm: helps restore blood flow by relaxing coronary smooth muscle.
• Peripheral vascular spasm: reduces arterial constriction during diagnostic angiography.
• Gastrointestinal spasm: eases intestinal smooth‑muscle contraction during endoscopic procedures.
• Urological smooth‑muscle spasm: facilitates catheter passage by relaxing ureteral smooth muscle.

• Papaverine acts as a non‑selective phosphodiesterase inhibitor, raising intracellular cyclic AMP and cyclic GMP levels in smooth‑muscle cells. The increased cyclic nucleotides inhibit calcium influx, leading to reduced contractile activity and relaxation of vascular and visceral smooth muscle.

Papaverine may cause a range of adverse reactions, most of which are dose‑dependent and reversible.

Common Side Effects

• Flushing: transient warmth and redness of the skin.
• Headache: mild to moderate intensity.
• Nausea: occasional feeling of queasiness.
• Hypotension: temporary drop in blood pressure.
• Dizziness: light‑headed sensation.
• Vaginal irritation (when used intravaginally): mild burning.

Serious or Rare Side Effects

• Severe hypotension: marked blood‑pressure fall requiring intervention.
• Cardiac arrhythmia: abnormal heart rhythm.
• Myocardial infarction: rare but possible ischemic event.
• Anaphylaxis: acute allergic reaction with airway compromise.
• Hepatic dysfunction: elevated liver enzymes.
• Seizures: rare neurologic event.

When using Papaverine, clinicians should consider several safety measures to minimize risk.

• Assess cardiovascular status: evaluate for existing heart disease before administration.
• Monitor blood pressure: watch for hypotensive episodes during and after dosing.
• Adjust for hepatic impairment: use lower doses in patients with liver dysfunction.
• Avoid concurrent vasodilators: limit additive blood‑pressure lowering effects.
• Review allergy history: ensure no known hypersensitivity to papaverine or excipients.
• Store at ambient temperature: keep below 25°C, in original packaging, protected from moisture.

Papaverine can interact with other medications, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Nitrates: combined use may cause profound hypotension.
• Beta‑blockers: additive blood‑pressure lowering effect.
• Calcium‑channel blockers: increased risk of cardiovascular depression.

Moderate Interactions (Monitor Closely)

• Anticoagulants: may enhance bleeding tendency.
• MAO inhibitors: potential for exaggerated vasodilatory response.
• Opioids: possible increase in central nervous system depression.