Valmiki Ramayana Sundara Kanda Sarga 36 Shloka 42

राघवः Rama, त्वद्गतेन thinking of you, अन्तरात्मना with heart, गात्रात् from his limbs, दंशान् flies, नैव अपनयेत् will not drive away, मशकान् mosquitoes, न not, कीटान् insects, न not, सरीसृपान् serpents, न not.

"Since you left, Rama has been always thinking sincerely of you, no longer drives away flies or mosquitoes nor insects or serpents from his body (his mind entirely fixed on you).