Duphalac Syrup Side Effects in Pakistan

A guide to the side effects of Duphalac Syrup, from common effects such as wind and diarrhoea to the warning signs that need a doctor.

Compiled by the PakVita Editorial Team · AI-assisted drafting with editorial review · Sourced from DRAP, WHO, BNF · Last updated: 2026-10-31 · Review date on file: 2026-10-31

A named review is not recorded for this page. Confirm medicine advice with your doctor or pharmacist.

Side Effects

Quick Answer

Common side effects of Duphalac Syrup (lactulose) are wind (flatulence), diarrhoea, stomach cramps, nausea and vomiting. Wind is common in the first few days and usually settles. Reduce the dose if diarrhoea occurs. Severe or persistent diarrhoea, dehydration or an allergic reaction needs medical help.

Side Effects at a Glance

Reported effects

Mild abdominal cramping
Flatulence
Nausea
Diarrhoea, especially at higher doses
Vomiting

Reactions needing medical advice

Severe allergic reactions
Persistent diarrhea leading to dehydration
Breathing issue

When to See a Doctor Immediately

Severe stomach pain
Persistent diarrhea leading to dehydration
Fainting
Difficulty breathing or swelling of the face, lips or tongue (get emergency help)

Duphalac Syrup Side Effects (Nuksanat)

Duphalac Syrup (Lactulose) is generally well tolerated at the correct dose. However, like all medicines, it can cause side effects in some patients.

Common Side Effects (Aam Nuksanat)

Mild abdominal cramping
Flatulence (wind), mainly in the first few days
Nausea
Diarrhoea, especially at higher doses
Vomiting

These side effects are usually mild. If diarrhoea occurs, reduce the dose. If side effects continue, inform your doctor.

Serious Side Effects (Sanjeedah Nuksanat)

Severe allergic reactions — see a doctor immediately
Persistent diarrhea leading to dehydration — see a doctor immediately
Breathing issue — see a doctor immediately

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

Severe stomach pain
Persistent diarrhea leading to dehydration
Fainting
Difficulty breathing or swelling of the face, lips or tongue (get emergency help)

Warnings and Precautions (Ihtiyat)

Do not use Duphalac Syrup if you are allergic to Lactulose or any component of the medicine
Individuals with galactosemia should not use this syrup
Patients with intestinal blockages

Side Effects Summary Table

Type	Side Effect	Action
Common	Flatulence	Usually settles in a few days
Common	Diarrhoea	Reduce the dose / inform doctor
Common	Mild abdominal cramping	Monitor / inform doctor
Common	Nausea	Monitor / inform doctor
Serious	Severe allergic reactions	See a doctor immediately
Serious	Persistent diarrhea leading to dehydration	See a doctor immediately

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. If you notice any side effect, contact your doctor or pharmacist.

Frequently Asked Questions

What are the most common side effects of Duphalac Syrup?

Wind (flatulence), diarrhoea, stomach cramps, nausea and vomiting. Wind is common in the first few days and usually goes away. If you get diarrhoea, the dose is usually too high and should be reduced.

Can Duphalac Syrup cause allergic reactions?

Rarely. Allergic reactions such as rash, itching or hives have been reported. Stop the syrup and get medical help immediately if you have swelling of the face or difficulty breathing.

Is Duphalac Syrup safe to take for a long time?

Long-term use should be under medical supervision. High doses used for a long time without adjustment can cause diarrhoea and loss of body salts (electrolytes).

What should I do if I experience side effects from Duphalac Syrup?

For wind or mild cramps, carry on; they often settle within a few days. For diarrhoea, reduce the dose. For severe or persistent diarrhoea, dizziness or an allergic reaction, stop the syrup and see a doctor.

Is Duphalac Syrup safe for people with diabetes?

The usual constipation dose is not expected to cause a problem for people with diabetes. The higher dose used for liver disease contains more sugar, so a doctor should take it into account.

Explore entries related to Duphalac Syrup by ingredient, class and listed uses. These links are not recommendations to switch treatment.

Same ingredient

Other entries for Lactulose. Form, strength and route can differ; ask a pharmacist before substituting.

Ingredient directory →

Lilac Syrup
Lactulose
SYRUPCheck formulation →

Other laxatives

Sibling medicines in the Laxatives class.

All in class →

Related by listed uses

Entries with overlapping constipation tags; they may address different diagnoses.

Constipation hub →

Sources

Duphalac 3.335 g/5 ml Oral Solution - Summary of Product Characteristics (SmPC) — electronic medicines compendium (emc)
DRAP Registered Product Data (Public Registry) — Drug Regulatory Authority of Pakistan
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.