Islamic scriptures contain a plethora of medical advice.
Cattle Dung and Urine
In Islamic texts, cattle dung and urine is described as a cure for most diseases.
The climate of Medina did not suit some people, so the Prophet ordered them to follow his shepherd, i.e. his camels, and drink their milk and urine (as a medicine). So they followed the shepherd that is the camels and drank their milk and urine till their bodies became healthy. Then they killed the shepherd and drove away the camels. When the news reached the Prophet he sent some people in their pursuit. When they were brought, he cut their hands and feet and their eyes were branded with heated pieces of iron.
A group of people from 'Ukl (tribe) came to the Prophet and they were living with the people of As-Suffa, but they became ill as the climate of Medina did not suit them, so they said, "O Allah's Apostle! Provide us with milk." The Prophet said, I see no other way for you than to use the camels of Allah's Apostle." So they went and drank the milk and urine of the camels, (as medicine) and became healthy and fat. Then they killed the shepherd and took the camels away. When a help-seeker came to Allah's Apostle, he sent some men in their pursuit, and they were captured and brought before mid day. The Prophet ordered for some iron pieces to be made red hot, and their eyes were branded with them and their hands and feet were cut off and were not cauterized. Then they were put at a place called Al-Harra, and when they asked for water to drink they were not given till they died. (Abu Qilaba said, "Those people committed theft and murder and fought against Allah and His Apostle.")
Narrated Abu Huraira:
The Prophet said, "If somebody keeps a horse in Allah's Cause motivated by his faith in Allah and his belief in His Promise, then he will be rewarded on the Day of Resurrection for what the horse has eaten or drunk and for its dung and urine."
Muhammad spat on dust, a dying man drank it and that healed the man. 
Muhammad spat in the eye of a blind man; the blind man regained his sight. 
During the battle of Khaybar Muhammad spat on the thigh wound of Salam ibn al Akwa’; this healed Salam ibn Akwa. 
Muhammad spat on the broken thigh of Ali ibn al Hakam; his thigh healed immediately. 
Muhammad spat on the severed hand of Mu’awwidh ibn Afra, the hand joined. 
Indian incense has long been used in ancient India by Hindus in their rituals, fundamentally for its healing properties, far before the advent of Islam. Incense is also used by Buddhists and practitioners of traditional Chinese religion for rituals. This remedy is acknowledged by Islam as a cure for several diseases.
Narrated Um Qais bint Mihsan:
I heard the Prophet saying, "Treat with the Indian incense, for it has healing for seven diseases; it is to be sniffed by one having throat trouble, and to be put into one side of the mouth of one suffering from pleurisy." Once I went to Allah's Apostle with a son of mine who would not eat any food, and the boy passed urine on him whereupon he asked for some water and sprinkled it over the place of urine.
Narrated Um Oais:
that she took to Allah's Apostle one of her sons whose palate and tonsils she had pressed to treat a throat trouble. The Prophet said, "Be afraid of Allah! Why do you pain your children by having their tonsils pressed like that? Use the Ud Al-Hindi (a certain Indian incense) for it cures seven diseases, one of which is pleurisy."
Muhammad says that four acts can reduce or eventually impair eye-sight. These are looking at unclean and impure objects, seeing one being hanged, looking at female private parts and sitting with the Ka'aba to one's backside.
Four things that reduce eye-sight are: to look at unclean and impure objects, to see one being hanged, to look at female private parts and to sit keeping Kaba behind
However it should be noted that losing eyesight (possibly due to over indulgence in the above mentioned activities) will earn one a place in paradise.
A few ansars (Islamic helpers) wanted to get blind because Muhammad said Allah has reserved paradise for a person whose two eyes are blind
Hearing is the only sensory that cannot be repaired / cured once damaged. Hence it's important for individuals to look after themselves and eliminate bad habits that can cause deafness. According to Islam, loving any materialistic object will cause not only deafness but also blindness
The Prophet (pbuh) said: "Your love for a thing causes blindness and deafness".
It should be noted that a place in paradise is reserved for blind people (read under eye sight).
Islamic scriptures instruct that the fly should be dipped into any consumable it settles on.
Allah's Apostle said, If a fly falls in the vessel of any of you, let him dip all of it (into the vessel) and then throw it away, for in one of its wings there is a disease and in the other there is healing (antidote for it) i. e. the treatment for that disease.
Cupping was a surgical technique used by the desert dwellers of medieval Arabia to heal certain illnesses. In this technique, using a sharp object such as a needle, an incision was made on certain part of the body, usually on the neck or on scalp. Then an experienced cupper would suck the incision to draw out the blood from the body. The Arabs believed that cupping would heal headache. Historical evidence suggests that Muhammad suffered from chronic migraines. He had to resort to regular cupping to reduce his pain. Cupping needed experienced cuppers. So Muhammad engaged a number of cuppers to perform this surgery. Some cuppers are even reported to have drank Muhammad’s blood.
Narrated Ibn 'Abbas:
The Prophet was cupped and he paid the wages to the one who had cupped him and then took Su'ut (Medicine sniffed by nose).
Narrated Jabir bin Abdullah:
I heard the Prophet saying, "If there is any healing in your medicines, then it is in cupping, a gulp of honey or branding with fire (cauterization) that suits the ailment, but I don't like to be (cauterized) branded with fire."
Honey has been specifically prescribed in Islam as a cure for loose motion. However it has to be noted that if symptoms persist, it's because the abdomen is bluffing, and not because the Islamic remedy has failed:
Narrated Abu Said:
A man came to the prophet and said, 'My brother has got loose motions'. The Prophet said, Let him drink honey." The man again (came) and said, 'I made him drink (honey) but that made him worse.' The Prophet said, 'Allah has said the Truth, and the abdomen of your brother has told a lie."
In Islam, Black cumin apparently is a cure for anything and everything, except death.
Narrated Khalid bin Sad:
We went out and Ghalib bin Abjar was accompanying us. He fell ill on the way and when we arrived at Medina he was still sick. Ibn Abi 'Atiq came to visit him and said to us, "Treat him with black cumin. Take five or seven seeds and crush them (mix the powder with oil) and drop the resulting mixture into both nostrils, for 'Aisha has narrated to me that she heard the Prophet saying, 'This black cumin is healing for all diseases except As-Sam.' Aisha said, 'What is As-Sam?' He said, 'Death."
In Islam, fever is caused solely because of the heat from hell that has radiated onto one's body. Hence, the temperature can be subsided by drinking water.
Abdullah bin 'Umar said, "The Prophet said, 'Fever is from the heat of Hell, so put it out (cool it) with water.' " Nafi' added: 'Abdullah used to say, "O Allah! Relieve us from the punishment," (when he suffered from fever).
Narrated Fatima bint Al-Mundhir:
Whenever a lady suffering from fever was brought to Asma' bint Abu Bakr, she used to invoke Allah for her and then sprinkle some water on her body, at the chest and say, "Allah's Apostle used to order us to abate fever with water."