Fine tremor of skeletal muscle, small increase in heart rate; urticaria; rash. Salbutamol: CNS stimulation, malaise, emotional lability, fatigue, nightmares, aggressive behavior, lightheadedness, disturbed sleep, irritability, bronchitis, nasal congestion, sputum increase, epistaxis, hoarseness, increased appetite, stomachache, muscle cramps & spasm, pallor, conjunctivitis, anorexia, teeth discoloration, dyspepsia, dilated pupils, epigastric pain, micturition difficulty, voice changes, angioedema, bronchospasm, oropharyngeal edema, erythema multiforme, SJS. Guaifenesin: Nausea, vomiting, GI discomfort, dizziness, headache.