Doxapram

Doxapram hydrochloride (marketed as Dopram, Stimulex or Respiram) is a respiratory stimulant. Administered intravenously, doxapram stimulates an increase in tidal volume, and respiratory rate.

Doxapram

Clinical data
Routes of administration	Intravenous
ATC code	R07AB01 (WHO)
Legal status
Legal status	In general: ℞ (Prescription only)
Identifiers
IUPAC name 1-ethyl-4- (2-morpholin-4-ylethyl)- 3,3-diphenyl-pyrrolidin-2-one
CAS Number	309-29-5
PubChem CID	3156
DrugBank	DB00561
ChemSpider	3044
UNII	94F3830Q73
KEGG	D07873
ChEBI	CHEBI:681848
ChEMBL	ChEMBL1754
CompTox Dashboard (EPA)	DTXSID2022963
ECHA InfoCard	100.005.653
Chemical and physical data
Formula	C24H30N2O2
Molar mass	378.516 g·mol^−1
3D model (JSmol)	Interactive image
SMILES O=C4N(CC)CC(CCN1CCOCC1)C4(c2ccccc2)c3ccccc3
InChI InChI=1S/C24H30N2O2/c1-2-26-19-22(13-14-25-15-17-28-18-16-25)24(23(26)27,20-9-5-3-6-10-20)21-11-7-4-8-12-21/h3-12,22H,2,13-19H2,1H3 Key:XFDJYSQDBULQSI-UHFFFAOYSA-N
(verify)

Mechanism of action

A vial of doxapram

Doxapram stimulates chemoreceptors in the carotid bodies of the carotid arteries, which in turn, stimulates the respiratory centre in the brain stem.

Appearance

Doxapram is a white to off-white, odorless, crystalline powder that is stable in light and air. It is soluble in water, sparingly soluble in alcohol and practically insoluble in ether. Injectable products have a pH from 3.5-5. Benzyl alcohol or chlorobutanol is added as a preservative agent in the commercially available injections.

Uses

Doxapram is used in intensive care settings to stimulate the respiratory rate in patients with respiratory failure. It may be useful for treating respiratory depression in patients who have taken excessive doses of drugs such as buprenorphine or fentanyl analogues which may fail to respond adequately to treatment with naloxone.[1]

It is equally as effective as pethidine in suppressing shivering after surgery.[2]

Side effects

Side effects include high blood pressure, panic attacks, rapid heart rate, tremor, sweating, and vomiting. Convulsions have been reported. Its use is relatively contraindicated in people with coronary heart disease, epilepsy, and high blood pressure. It is also contraindicated in newborns and small children, mainly due to the presence of benzyl alcohol, which is included as a preservative.

See also

• Pentethylcyclanone (similar structure)

References

1. Buprenorphine Drug Data Sheet
2. Singh P, Dimitriou V, Mahajan RP, Crossley AW (November 1993). "Double-blind comparison between doxapram and pethidine in the treatment of postanaesthetic shivering". British Journal of Anaesthesia. 71 (5): 685–8. doi:10.1093/bja/71.5.685. PMID 8251281.