This is a question about Ramayana. In the battle between Rama and Ravana, Lakshmana was struck with an arrow shot by Meghnad, the son of Ravana. Lakshmana became unconscious. Which healer was then called by Rama ?
Sushena, a monkey physician tested Lakshmana when he was hit by a shakti by Ravana (not Meghanad. It is according to Ramcharitmanas, Lakshmana was hit by Mefhnad).
When Sri Rama was worried and heart broken that Lakshmana was hit by Ravana, he laments and gets ready to die like his brother (Sri Rama thought Lakshmana died). Then Sushena, the physician of Vanaras said these comfortable words to Rama.
From Yuddha Kanda Sarga 101 of Valmiki Ramayana,
राममेवं ब्रुवाणं तु शोकव्याकुलितेन्द्रियम् || ६-१०१-२४
आश्वासयन्नुवाचेदं सुषेणः परमं वचः |
Comforting Rama, whose mind was full of grief and who was thus lamenting, Sushena, for his part, addressed the following excellent words:
नैव पञ्चत्वमापन्नो लक्ष्मणो लक्ष्मिवर्धनः || ६-१०१-२६
न ह्य्स्य विकृतं वक्त्रं न च श्यामत्वमागतम् |
"Lakshmana, the augmenter of prosperity, has not got into death. His countenance is not changed, nor has it become dark."
His face may be seen with a good brightness and very much placid. The palms of his hands are resembling the petals of a lotus. His eyes too are very bright."
He is the one who prescribed the life bringing herbs and asked Hanuman to bring them quickly. He gives different herbs names for different purposes. But Hanuman could not identify those precious herbs. So, he uprooted the whole Oushadhi mountain and restored it back to its original position after the mission is over.
Hanuman brought the mountain twice. He also brought them once to bring back the lives of dead and wounded Vanaras. The first instance is when the most of the Vanaras including Rama and Lakshmana fell unconscious due to the effect of Brahmastra shot by Indrajeet. Then Jambavan prescribes it and asks Hanuman to bring the herbs because the physician Suṣeṇa was also unconscious. This is said in Sarga 74 of Valmiki Ramayana.
So, for the first time when whole army fell down, it was Jambavan who prescribed. When Lakshmana alone fell unconscious, it was Sushena, the physician.
According to Ramcharitmanas, a fierce battle took place between Lakshmana and Indrajit. Indrajit throws a javelin into the chest of Lakshmana. He was wounded severely and fell unconscious. Jambavan says to bring Sushena and Sushena prescribes Sanjivani.
Jåmbavån said, Suṣeṇa, the physician, lives in Lankå; someone should be sent to fetch him here. Assuming a minute (indiscernible) form Hanumån went and immediately brought him, house and all. Doha 54 Chaupai 4
rāmapadārabinda sira nāyau āyi suśena |
kahānāmagiri auṣadhī jāhu pavānāsuta lenā
Suṣeṇa came and bowed his head at Lord Råma's lotus-feet. He mentioned the name of the herb as well as of the mountain where it could be had, and said, "Proceed, O son of the wind-god, to bring it. Doha 55
So, It is Sushena in Ramcharitmanas also. But he is not said as Vanara.
Sanjeevani was prescribed by Jambavan, see the reference below about the conversation between Jambavan and Hanuman:
Thereafter, that Jambavan of great splendour spoke to Hanuma as follows: "Come on, O foremost of monkeys! You ought to protect the lives of monkeys."
"O Hanuma! You ought to go to Himalaya, the foremost of mountains, by traveling higher and higher over the large ocean."
"O annihilator of enemies! Thereafter, you will see there the Mount Rishabha, the excellent mountain and the very much powerful peak of Kailasa, with a golden hue."
"O foremost of monkeys! Sprouted on the head of that mountain, are four blazing herbs. You can see them, illuminating the ten quarters."
"You can see there, Mrita Sanjivani (capable of restoring the dead to life), Vishalyakarani (capable of extracting weapons and healing all wounds inflicted by weapons), Suvarnakarani (restoring the body to its original complexion) and Sandhani, the great herb (capable of joining severed limbs or fractured bone)."