Sildenafil (Viagra) Side Effects in Pakistan

Complete guide to Sildenafil side effects — from common mild effects to serious emergencies, particularly nitrate interaction and priapism. Seek medical help immediately for any serious symptom.

Compiled by the PakVita Editorial Team · AI-assisted drafting with editorial review · Sourced from DRAP, WHO, BNF · Last updated: 2026-06-17

Side Effects

Quick Answer

Common side effects of Sildenafil (Viagra) include headache, flushing, dyspepsia, nasal congestion, visual colour tinge (bluish), and dizziness. Serious emergencies include: fatal hypotension if taken with nitrates, priapism (erection >4 hours — emergency), NAION sudden vision loss, and sudden hearing loss. If you take nitrate heart medicines and experience severe BP drop — call emergency services immediately.

Side Effects at a Glance

Common

Headache (sir dard — most common, usually mild)
Flushing
Dyspepsia
Nasal congestion (naak band hona)
Visual colour tinge (bluish/greenish hue — temporary, especially at higher doses)
Dizziness

Serious — See a Doctor

Fatal hypotension with nitrates (heart medicines) — sudden severe BP drop — LIFE-THREATENING EMERGENCY
Priapism (painful erection lasting >4 hours) — EMERGENCY — permanent erectile damage if not treated promptly
NAION (non-arteritic anterior ischaemic optic neuropathy) — sudden painless vision loss in one or both eyes — EMERGENCY
Sudden hearing loss or severe tinnitus — EMERGENCY

When to See a Doctor Immediately

Chest pain during or after use — possible cardiac event or nitrate interaction — EMERGENCY (call ambulance)
Erection lasting >4 hours (priapism) — EMERGENCY
Sudden vision loss in one or both eyes — EMERGENCY (stop medicine, go to hospital)
Sudden hearing loss or severe tinnitus — EMERGENCY (stop medicine, go to hospital)
Severe dizziness or fainting — urgent care

Sildenafil (Viagra) Side Effects (Nuksanat)

Sildenafil (Viagra) is well-tolerated in most men at correct doses. However, it is important to be aware of a few serious emergencies — especially nitrate interaction.

Common Side Effects (Aam Nuksanat)

Headache (sir dard) — most common
Flushing
Dyspepsia (indigestion)
Nasal congestion (naak band hona)
Visual colour tinge (bluish/greenish hue — temporary, dose-dependent)
Dizziness

These side effects are generally mild and resolve within a few hours.

Serious Side Effects (Sanjeedah Nuksanat — EMERGENCY)

Hypotension with nitrates — chest pain, severe dizziness, fainting — LIFE-THREATENING — AMBULANCE
Priapism (>4 hours erection) — painful or painless — EMERGENCY — Permanent damage risk
NAION (sudden vision loss) — one or both eyes — EMERGENCY
Sudden hearing loss / severe tinnitus — EMERGENCY

When to See a Doctor (Kab Doctor Se Milna Zaroori Hai)

Chest pain during/after use + nitrate use history — EMERGENCY AMBULANCE
Erection >4 hours — EMERGENCY ROOM
Sudden vision loss — EMERGENCY ROOM
Sudden hearing loss or severe tinnitus — EMERGENCY ROOM
Severe dizziness or fainting — urgent care

Warnings and Precautions (Ihtiyat)

NEVER take with nitrates — absolute contraindication
Purchase only from a licensed pharmacy — counterfeit tablets may contain unknown ingredients
Limit alcohol — enhanced BP drop

Side Effects Summary Table

Type	Side Effect	Action
Common	Headache	Monitor; usually resolves
Common	Flushing	Monitor; usually resolves
Common	Dyspepsia	Antacid / inform doctor
Common	Blue/green vision tinge	Temporary — if vision LOSS occurs, EMERGENCY
EMERGENCY	Hypotension with nitrates	Ambulance IMMEDIATELY
EMERGENCY	Priapism (>4 hrs)	Emergency room IMMEDIATELY
EMERGENCY	Sudden vision loss (NAION)	Stop + Emergency room
EMERGENCY	Sudden hearing loss	Stop + Emergency room

Reporting Side Effects

If you notice any unexpected side effect, report it on the DRAP pharmacovigilance portal: https://www.dra.gov.pk/pharmacovigilance

The information in this guide is for educational purposes only. For any serious symptom, contact a doctor or emergency services immediately.

Frequently Asked Questions

Sildenafil ke sabse common side effects kya hain?

Most common: headache, flushing, dyspepsia, nasal congestion, bluish tinge in vision, and dizziness. These are generally mild and resolve within a few hours.

Vision mein blue color dikh raha hai — kya karein?

A bluish or greenish tinge is a known minor side effect of sildenafil (due to PDE6 inhibition) — it is temporary and usually resolves within a few hours. However, if SUDDEN VISION LOSS occurs, this may indicate NAION — go to the emergency room immediately.

Priapism kya hai aur kya karein?

Priapism — an erection lasting more than 4 hours — is a MEDICAL EMERGENCY. Go to the emergency room immediately. Delay can cause permanent erectile damage. Do not attempt to treat it at home alone.

Nitrates aur sildenafil sath le lein to kya karein?

This combination can cause life-threatening hypotension. If taken together accidentally and you experience a drop in BP, chest pain, dizziness, or fainting — CALL AN AMBULANCE IMMEDIATELY — this is an EMERGENCY. Do not drive yourself.

Kya sildenafil hearing ya vision ko permanently damage karta hai?

Permanent damage is rare but possible. NAION sudden vision loss (rare, usually one eye) and sudden hearing loss have been reported. If either occurs, stop the medicine immediately and seek emergency care — the sooner treatment begins, the better the prognosis.

Brand alternatives, same-class options, and other medicines used for the same conditions as Sildenafil Tablet (Viagra).

Used for the same conditions

Other medicines commonly used for headache and overlapping conditions.

Headache hub →

Sources

DRAP Registered Products Database — Drug Regulatory Authority of Pakistan
WHO Model List of Essential Medicines, 23rd ed. (2023) — World Health Organization
British National Formulary (BNF) — BMJ Group & Pharmaceutical Press

Medical disclaimer

This page is for educational use only and does not replace professional medical advice. Always confirm diagnosis, dose, and interactions with a qualified doctor or pharmacist before starting or changing any medicine.