Yaman Ezzedin is one of several desperately ill children in the rebel-held town under regime siege outside Damascus in need of immediate evacuation to a well-equipped hospital.
And he is one of some 40,0000 residents who have been affected by food and medicine shortages inside Madaya since the regime encircled the town two years ago and besieged it completely last summer.
The town grabbed international attention in late 2015 after reports its residents were starving to death because of a lack of food.
A 10-year-old Syrian girl shot in Madaya was evacuated on Sunday to a Damascus hospital after an online campaign, but another dozen children remain inside the town in urgent need of medical care.
This week, activists inside Madaya posted a video of Yaman on social media as part of a plea for help for the children.
"He won't stop crying the pain is so unbearable," his father Alaa tells AFP by phone.
Cold compresses have done nothing to bring down his temperature, Alaa says, or alleviate convulsions, hallucinations and an intolerance of sunlight.
The young boy is so consumed by the pain, "he no longer recognises us," his father says, his voice breaking.
"I don't know who to ask... I call on the whole world, the United Nations, the Red Crescent to save my son."
- One field hospital -
Some 86 people have died in a year-long government siege of Madaya, including 65 from starvation and malnutrition, two NGOs said last month.
The Syrian American Medical Society and Physicians for Human Rights blamed the deaths on the government's "stranglehold" on the town.
The United Nations says nearly 600,000 Syrians are living under siege, mostly imposed by the government, though the tactic has also been used by rebel fighters and the Islamic State group.
Thirteen children including Yaman -- as well as a semi-paralysed, blind 22-year-old -- urgently need to be evacuated out of the town, according to medics.
Madaya only has "one field hospital, which offers modest services owing to the lack of medication and equipment," a group of health professionals said in a Facebook post on Tuesday.
Signup to our newsletter and follow us on Facebook and Twitter!
"Everyone without exception suffers from a lack of calcium... and many are malnourished," they said.
The group said 45 cases of typhoid had been recorded, "most... among women and children, with no medication or antibiotics to assist in treatment.
"These cases are in dire need of hospitalisation outside of Madaya somewhere equipped and capable of offering treatment before time runs out," they said.
On Thursday, the UN's Syria envoy called for 16 people -- mostly children and the youngest just six months old -- to be allowed out of Madaya for medical treatment.
Staffan de Mistura also called for the evacuation of another two people from Fuaa, a rebel-besieged village in the northwestern Idlib province.
- Two dentists, one vet -
Under a deal signed last September, any evacuation from the regime-encircled towns of Madaya and Zabadani must be matched by a similar operation from the rebel-besieged Shiite villages of Fuaa and Kafraya.
Dentist Mohammad Darwish is one of just three acting doctors left in Madaya.
Under blockade, the 25-year-old, another dentist and a vet have had to become surgeons, performing operations including caesarians and amputations to help the town's ailing residents.
One of the worst cases he has seen is that of Bissan al-Shamaa, not yet one year old, whose parents unknowingly fed her milk formula that had been mixed with plaster powder.
"She's suffering from septicaemia," a blood infection, he says.
Activists inside the town this week posted a picture of Bissan among a series of images of children in urgent need of medical help.
On the local council's Facebook page, nine-month-old Bissan appears with her large eyes lifeless and tiny body emaciated.
The caption says she is suffering from severe malnutrition after her mother mixed her milk powder with starch.
"May God prevent all parents from seeing their child in such a state," Yaman's father says.