Educational information, not medical advice.See how evidence is graded

Post-e-Kunain (Sinchona)

Do not self-treat with Post-e-Kunain (Sinchona)

If this is an emergency

Some reactions to Post-e-Kunain (Sinchona) need urgent care. Call your local emergency number or go to an emergency department straight away — do not wait to see whether it passes.

Who should avoid Post-e-Kunain (Sinchona)?

When should you see a doctor?

Stop taking it and get medical help the same day if your ears start ringing, your hearing dulls, or your sight goes blurry or loses colour.

Go to an emergency department now if you have any of these:

Bleeding you cannot stop, blood in your urine or stool, or bruises coming up for no reason. A fast, slow or uneven heartbeat, chest pain, or fainting. Shaking, sweating and confusion, which can mean your blood sugar has dropped too low. Dark or red urine, or passing much less urine than usual. Swelling of the lips, face or throat, or trouble breathing.

If someone has taken too much, call your local poison centre or emergency number straight away, even if they look well. Take the packet with you.

And if you have a fever after travel to a place where malaria spreads, see a doctor within 24 hours. Malaria can turn severe fast.

Educational information, not medical advice — ask your doctor or midwife.

What is Post-e-Kunain (Sinchona)?

Post-e-Kunain is the dried bark of the cinchona tree (Cinchona officinalis). It is also called cinchona bark. Unani and Persian healers use it for fever with chills, for weak appetite, and as a bitter tonic.

This is not a mild kitchen herb. The bark is the source of quinine, the first drug that worked against malaria. The gap between a helpful dose and a harmful one is small.

Here is the short verdict. Pure quinine has been tested in people for many years and is a licensed medicine. The raw bark has not been tested that way.

Long use in a tradition is not proof that a remedy works. That holds here.

Because the bark carries drug-strength compounds, we treat it as a high-risk item. It can thin the blood, upset the heartbeat, drop blood sugar and damage the kidneys. People have died from too much quinine.

Read the safety part of this page before you read anything else about doses.

How does Post-e-Kunain (Sinchona) work?

The bark holds quinine and other alkaloids (strong plant compounds). Quinine kills the parasite that causes malaria. That part is well proven, but it was proven with the pure drug, not with bark tea.

The bark is also very bitter. In Unani thought, a bitter taste wakes up the stomach and helps clear a 'cold' fever. Bitter taste does seem to raise saliva and gut juices in people, but how much that helps digestion is not clear.

Quinine also acts on muscle cells. It makes them slower to fire. That is the idea behind its old use for leg cramps.

One more point matters. The amount of quinine in bark shifts from tree to tree and batch to batch. So the strength of any home-made bark drink is hard to guess.

What forms does Post-e-Kunain (Sinchona) come in?

You may see it as rough bark pieces or as a fine brown powder.

Other common forms are a decoction (bark boiled in water) and a tincture (a liquid extract made with alcohol). Unani shops also sell mixed pills and syrups that contain the bark.

Pure quinine tablets are a licensed medicine, not a herbal product. They are made to a set strength. Bark products are not.

Tonic water holds a tiny amount of quinine as a flavour. That amount is set by food law and is far below a medicine dose.

Where it comes from:

The cinchona tree grows in the Andes of South America. Quechua people used the bark long before Europeans arrived. Jesuit priests carried it to Europe in the 1600s, where it was called Jesuit's bark.

Traders moved it east along the same routes as spices and cloth. Persian and Unani doctors took it up as a fever bark and kept the name kunain.

By the 1800s it was a standard fever drug in Unani practice and in Europe alike. It is a late arrival in these books, but a deeply rooted one.

What does Post-e-Kunain (Sinchona) help with?

What are the side effects of Post-e-Kunain (Sinchona)?

Good to know:

Mild effects are common. Ringing ears, headache, sick stomach and blurred sight together are called cinchonism, and they are the body's early warning that the dose is too high.

The serious effects are rarer but they are not freak events. Low platelets and bleeding can start after a single small dose in someone who reacts badly. Quinine overdose can stop the heart or take a person's sight for good.

Stop the bark at the first sign of ringing ears, easy bruising or a change in your vision.

Options to discuss with a clinician

For each of the reasons people reach for cinchona bark, there are routes that have been studied properly — and every one of them starts as a conversation with a doctor or pharmacist rather than a straight swap.

**Fever with chills, or suspected malaria.** Any fever with shaking chills after travel to a malaria area is an emergency: same-day assessment, a blood test that confirms or rules out the parasite, and prescribed antimalarial treatment matched to the species and your medical history. A clinician can also find the other causes of fever that look identical.

**Night-time leg cramps.** Worth raising with a GP or pharmacist, who can check for causes such as medicines you already take, circulation problems, nerve issues or low thyroid function, and talk through stretching and sleep-position approaches that have been trialled.

**Poor appetite and weak digestion.** Ask a clinician to look for a reason — reflux, medication side effects, low mood, thyroid or dental problems — before anything is added. A registered dietitian can help if eating has dropped off.

**Tiredness after illness.** A doctor can check blood count, iron, thyroid and glucose, and advise on a graded return to activity.

If you want a traditional approach, a qualified Unani practitioner working alongside your doctor can discuss what fits safely.

Graded pages for the options named above:

Review status

This page has not been signed off by a pharmacist and is not published. It is shown here for a policy decision only.