It may also result in reoccurrence of the condition that is being treated. Rarely tardive dyskinesia can occur when the medication is stopped. Overdose
Symptoms
Symptoms are usually due to side effects. Most often encountered are:

Anticholinergic side effects (dry mouth, constipation, paralytic ileus, difficulties in urinating, decreased perspiration)
Coma in severe cases, accompanied by respiratory depression and massive hypotension, shock
Hypotension or hypertension
Rarely, serious ventricular arrhythmia (torsades de pointes), with or without prolonged QT-time
Sedation
Severe extrapyramidal side effects with muscle rigidity and tremors, akathisia, etc. Treatment
Treatment is mostly symptomatic and involves intensive care with stabilization of vital functions. In early detected cases of oral overdose, induction of emesis, gastric lavage, and the use of activated charcoal can be tried. In the case of a severe overdose, antidotes such as bromocriptine or ropinirole may be used to treat the extrapyramidal effects caused by haloperidol, acting as dopamine receptor agonists. ECG and vital signs should be monitored especially for QT prolongation and severe arrhythmias should be treated with antiarrhythmic measures. Prognosis
An overdose of haloperidol can be fatal, but in general the prognosis after overdose is good, provided the person has survived the initial phase. Pharmacology
Haloperidol is a typical butyrophenone type antipsychotic that exhibits high affinity dopamine D2 receptor antagonism and slow receptor dissociation kinetics. It has effects similar to the phenothiazines. The drug binds preferentially to D2 and α1 receptors at low dose (ED50 = 0.13 and 0.42 mg/kg, respectively), and 5-HT2 receptors at a higher dose (ED50 = 2.6 mg/kg).
It is difficult to quantify by subjective complaints or clinical examinations alone, hence both clinicians and researchers depend both on concurrent subjective assessment and on objective measurement of the nasal airway.Prevalence of  kyphosis has been linked to nasal obstruction in a study. Treatment
According to WebMD, congestion can be addressed through the use of a humidifier, warm showers, drinking fluids, using a neti pot, using a nasal saline spray, and sleeping with ones head elevated. It also recommends a number of over the counter decongestants and antihistamines. A 2012 study concluded that combining nasal sprays with "nasal breathing exercises" (NBE) led to improvement of symptoms. Though it may seem weird, crying can also be helpful.The Cleveland Clinic also states that congestion may be a sign of a deviated septum, a condition that needs to be addressed by a doctor. See also
Decongestant
Honeymoon rhinitis
Inhaler

References
Further reading
Nestor, James (2020). Breath: The New Science of a Lost Art. Riverhead Books. ISBN 978-0735213616. == External links ==