The effects of smoked marijuana on metabolism and respiratory control.

Marijuana is a sedative, and most sedatives are respiratory depressants. However, the ventilatory effects of marijuana are unknown. In a placebo-controlled study of 8 subjects, smoking marijuana significantly increased ventilation and hypercapnic ventilatory response. Peak effects occurred 15 min after smoking, when ventilation increased from 7.4 +/- 0.39 (mean +/- SE) to 10.4 +/- 1.41 liter per min (P less than 0.01), whereas hypercapnic ventilatory response, measured as the slope of the relationship of ventilation to CO2, increased from 2.7 +/- 0.28 to 5.4 +/- 1.02 liter per min per mm Hg (P less than 0.05). Blood pH, PCO2, and ventilatory response to hypoxia were unchanged. Changes in ventilation usually parallel changes in metabolic rate. Smoked marijuana caused an increase in metabolic rate that also peaked after 15 min. Pretreatment with propranolol completely abolished the increase in hypercapnic ventilatory response, but did not affect the other changes. Thus, smoked marijuana had stimulatory effects on metabolic rate, ventilation, and the ventilatory response to CO2. The latter appears to be mediated by the beta sympathetic nervous system.

[1]  D. Tashkin,et al.  Bronchial effects of aerosolized delta 9-tetrahydrocannabinol in healthy and asthmatic subjects. , 2015, The American review of respiratory disease.

[2]  J. Weil,et al.  Effects of hypermetabolism on ventilation and chemosensitivity. , 1977, The Journal of clinical investigation.

[3]  Weil Jv,et al.  Effects of hyperthermia on hypoxic ventilatory response in normal man. , 1977 .

[4]  D. Flenley,et al.  Effect of intravenous infusion of salbutamol on ventilatory response to carbon dioxide and hypoxia and on heart rate and plasma potassium in normal men. , 1976, British medical journal.

[5]  D. Tashkin,et al.  Subacute effects of heavy marihuana smoking on pulmonary function in healthy men. , 1976, The New England journal of medicine.

[6]  R. Weiskopf,et al.  Ventilatory interaction between hypoxia and [H+] at chemoreceptors of man. , 1975, Journal of applied physiology.

[7]  T. C. Smith,et al.  Intravenous Δ9‐Tetrahydrocannabinol: Effects on Ventilatory Control and Cardiovascular Dynamics , 1975 .

[8]  K. Aqleh,et al.  Respiratory effects of delta‐9‐tetrahydrocannabinol , 1975, Clinical pharmacology and therapeutics.

[9]  R. Noyes,et al.  Analgesic Effect of Delta‐9‐Tetrahydrocannabinol , 1975, Journal of clinical pharmacology.

[10]  B. Whipp,et al.  Cardiodynamic hyperpnea: hyperpnea secondary to cardiac output increase. , 1974, Journal of applied physiology.

[11]  D. Tashkin,et al.  Acute pulmonary physiologic effects of smoked marijuana and oral (Delta)9 -tetrahydrocannabinol in healthy young men. , 1973, The New England journal of medicine.

[12]  E. Gaensler,et al.  Single-dose effects of marihuana smoke. Bronchial dynamics and respiratory-center sensitivity in normal subjects. , 1973, The New England journal of medicine.

[13]  G F Filley,et al.  Augmentation of chemosensitivity during mild exercise in normal man. , 1972, Journal of applied physiology.

[14]  W. Roth,et al.  Effects on Humans of ▵9-Tetrahydrocannabinol Administered by Smoking , 1972, Science.

[15]  W. Roth,et al.  Effects on humans of A9-trahydrocannahiiioI administered by smoking. , 1972 .

[16]  J. Dempsey,et al.  Estimation of arterial PO2, PCO2, pH, and lactate from arterialized venous blood. , 1972, Journal of applied physiology.

[17]  W. O. Friesen,et al.  Hypoxic ventilatory drive in normal man. , 1970, The Journal of clinical investigation.

[18]  J. Weil,et al.  A modified fuel cell for the analysis of oxygen concentration of gases. , 1967, Journal of applied physiology.

[19]  T. Biscoe,et al.  Factors affecting the cat carotid chemoreceptor and cervical sympathetic activity with special reference to passive hind‐limb movements , 1967, The Journal of physiology.

[20]  Read Dj,et al.  A clinical method for assessing the ventilatory response to carbon dioxide. , 1967 .

[21]  A. G. Ramsay.  Effects of metabolism and anesthesia on pulmonary ventilation. , 1959, Journal of applied physiology.