The autism spectrum is a range of neurodevelopmental conditions generally characterized by difficulties in social interactions and communication, repetitive behaviors, intense interests, and unusual responses to sensory stimuli. It is commonly referred to as autism or, in the context of a professional diagnosis, autism spectrum disorder (ASD), but the latter term remains controversial among neurodiversity advocates, neurodiversity researchers, and many autistic people due to the use of the word disorder and due to questions about its utility outside of diagnostic contexts.A spectrum disorder is one that can manifest very differently from person to person: any given person with the disorder is likely to show some but not all of the characteristics associated with it, and may show them to very different degrees. Different autistic people might show strikingly different characteristics, and the same person might also present differently at different times. Historically, the autism spectrum was divided into sub-categories, but questions persisted over the validity of these divisions. The most recent editions of the major English-language diagnostic manuals, Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR, published in 2022) and International Classification of Diseases (ICD-11, released in 2021) both list ASD as a single disorder.Given concerns about the appropriateness of the term disorder, many sources prefer to use the word "autism" without any additional words, on the basis that this is the least controversial term among people with different perspectives or (in the United Kingdom) autism spectrum conditions (ASC) rather than ASD.
Given that antagonism of D2 receptors is more beneficial on the positive symptoms of schizophrenia and antagonism of 5-HT2 receptors on the negative symptoms, this characteristic underlies haloperidols greater effect on delusions, hallucinations and other manifestations of psychosis. Haloperidols negligible affinity for histamine H1 receptors and muscarinic M1 acetylcholine receptors yields an antipsychotic with a lower incidence of sedation, weight gain, and orthostatic hypotension though having higher rates of treatment emergent extrapyramidal symptoms. Haloperidol acts on these receptors: (Ki)

D1 (silent antagonist) – Unknown efficiency
D5 (silent antagonist) – Unknown efficiency
D2 (inverse agonist) – 0.7 nM
D3 (inverse agonist) – 0.2 nM
D4 (inverse agonist) – 5–9 nM
σ1 (irreversible inactivation by haloperidol metabolite HPP+) –  3 nM
σ2 (agonist): 54 nM
5HT1A receptor agonist –  1927 nM
5HT2A (silent antagonist) –  53 nM
5HT2C (silent antagonist) – 10,000 nM
5HT6 (silent antagonist) – 3666 nM
5HT7 (irreversible silent antagonist) – 377.2 nM
H1 (silent antagonist) – 1,800 nM
M1 (silent antagonist) – 10,000 nM
α1A (silent antagonist) – 12 nM
α2A (silent antagonist) – 1130 nM
α2B (silent antagonist) – 480 nM
α2C (silent antagonist) – 550 nM
NR1/NR2B subunit containing NMDA receptor (antagonist; ifenprodil site): IC50 – 2,000 nM

Pharmacokinetics
By mouth
The bioavailability of oral haloperidol ranges from 60 to 70%. However, there is a wide variance in reported mean Tmax and T1/2 in different studies, ranging from 1.7 to 6.1 hours and 14.5 to 36.7 hours respectively. Intramuscular injections
The drug is well and rapidly absorbed with a high bioavailability when injected intramuscularly. The Tmax is 20 minutes in healthy individuals and 33.8 minutes in patients with schizophrenia.