Clinical beta

FMBM is currently in clinical beta. Content is for professional review/testing and must not replace local protocols, senior clinical judgment, or official prescribing references.

Drug Monograph

Dipyridamole

Antiplatelet / vasodilator (adenosine reuptake inhibitor)

StrokePOIVAdult

Indication

Secondary stroke prevention (combo) • Stress test (IV)

At a glance

INDICATIONS (CORE USE)

Often with aspirin (ER combo) secondary stroke prevention; **IV** for pharmacologic stress imaging.

ADULT DOSE (STANDARD)

ER capsule **200 mg BID** (aspirin 25 mg fixed combo) OR IV stress per nuclear protocol

MAX DOSE

Per combo product

Route

PO ER; IV (stress)

PEDIATRIC DOSE

Not first-line

Do not miss

Must-not-miss safety points

Major warning

- **Hypotension** vasodilation - **Bleed** with aspirin component or anticoagulants - Headache common — adherence

Indications

USE IF: Secondary stroke prevention when combo indicated. AVOID IF: Hemodynamic instability without monitoring, bronchospasm risk IV stress.

Primary

Secondary stroke prevention (aspirin–dipyridamole ER)

Secondary

Pharmacologic stress testing (IV)

Dosing

STANDARD (ADULT PO)

200 mg dipyridamole / 25 mg aspirin BID (ER capsule) — swallow whole

ADULT DOSE

IV dosing by cardiology/nuclear medicine only.

PEDIATRIC DOSE

N/A

MAX DOSE

Per ER product

Practical Note

Do not crush ER capsule.

Warnings

Clinical warnings

**Major bleeding** (GI, ICH, post-procedural) — higher with **DAPT**, triple therapy, renal failure, age — counsel early symptoms
Coronary steal phenomenon stress test
headache

Adverse effects

Headache
hypotension
GI upset
bleeding (combo)

Contraindications

**Active major bleeding** — hold until controlled unless embedded in explicit procedural plan
**Uncontrolled hypotension** or critical aortic stenosis (vasodilator caution) — clinical judgment
Hypersensitivity

Drug interactions

**Add anticoagulant or second antiplatelet** → **reassess bleed risk** + BP (vasodilator stack)
Adenosine
theophylline
antihypertensives
anticoagulants

Special populations

Pediatrics

Not first-line

Pregnancy

Avoid unless benefit clear

Lactation

See lactation references and product labeling.

Renal impairment

Severe renal impairment — caution oral; IV stress separate **Renal:** severe impairment — use oral ER forms with caution per label; stress-test IV dosing separate pathway

Hepatic impairment

Hepatic impairment — caution

Elderly

Orthostatic hypotension

Administration

ER PO whole; IV in monitored suite

Monitoring

Monitor: - **Orthostatic symptoms** → review other vasodilators/antihypertensives - **IV stress dose** → bronchospasm caution in asthma — separate from oral monitoring - BP with vasodilator stack
Recheck: - **Bleed symptoms** on aspirin combo or with anticoagulant → **hold + reassess** - New or worsening **bleeding**, unexplained **Hb drop**, or planned invasive procedure within **48–72h** → reassess antiplatelet plan with cardiology/surgery when on DAPT - If targets not met after reassessment of dose, organ function, and interactions → escalate per protocol (DO NOT continue blindly)

Overdose / toxicity

Clinical Picture

**Overdose:** hypotension, flushing, tachycardia, bleeding if combined with anticoagulants. **Therapeutic:** headache common.

Immediate Actions

Supportive; IV fluids if hypotensive; hold further doses

Antidote

No specific antidote; treat complications (supportive care, platelets / hemostasis per protocol, anaphylaxis → epinephrine per ACLS)

Decontamination

Charcoal if early large ingestion

Escalation

Shock refractory to fluids → **ICU**

Clinical pearls

Common mistakes, resistance logic, and bedside traps

High-Yield Summary

**Aggrenox = aspirin + dipyridamole** — double bleed teaching. → Headache drops adherence.

Clinical pearls

IV dipyridamole stress — bronchospasm kit ready. *Antiplatelet (all agents):* **Primary vs secondary (aspirin):** primary **not routine**; secondary **strong** when guideline-supported. **DAPT:** **do not stop early** post-stent without expert; duration **ACS vs stable CAD**; procedures need **explicit review**. **Bleeding-first:** GI/ICH/peri-op; **duplicate/hidden aspirin** on med rec. **Aspirin toxicity** (salicylate) is a **separate pathway** from antiplatelet bleed.

Antiplatelet safety

Combo product ID
Orthostasis
Headache counseling

Pharmacokinetics

ER formulation for stroke prevention; IV for short stress exposure.

Mechanism of action

↑ cAMP platelet inhibition + adenosine vasodilation.

Common brand names

Saudi Arabia

Persantine, Dipyridamole

Global

Aggrenox component, (placeholder — verify local product)

Common trade names are curated examples only — formulations and availability vary. Verify the exact product name with your local pharmacy and national regulator before prescribing or dispensing.

Country practice notes

DAPT duration and perioperative management follow **ESC/AHA/ACC** and local cardiology consensus — not one-size rules.
Primary prevention aspirin thresholds differ by guideline and age — verify regional primary-care policy.

References

Saudi Arabia

SFDA (Saudi Food & Drug Authority)
Saudi National Formulary / MOH (where available)

International

WHO Model List of Essential Medicines (verify current edition)
US FDA or EU EMA product information (when national SmPC is unavailable)
ACC / AHA / ESC cardiovascular guidelines (CAD, ACS, PCI)
FDA / SFDA product labeling
Local cath lab / antithrombotic protocol
ACC / AHA / ESC cardiovascular guidelines (CAD, ACS, PCI)
FDA / SFDA product labeling
Local cath lab / antithrombotic protocol

Do not miss

Document antiplatelet indication (primary vs secondary prevention vs stent DAPT)
Med reconciliation: OTC aspirin, NSAIDs, fish oil, anticoagulants
**GI / ICH bleed stack:** With aspirin (**Aggrenox**) or anticoagulants — **reassess necessity**; counsel alarm symptoms.
**Hypotension:** Vasodilator — watch standing BP with other antihypertensives.
**Asthma:** IV dipyridamole stress — bronchospasm risk.
Calling it “just aspirin” — it is **combination**.
Combo product ID
Orthostasis
Headache counseling