Karachi, Pakistan, and Bogota, Colombia — Around the world, this newspaper has found people who are fighting back: * So desperate is rising heroin addiction in crowded, hot Karachi that several hundred mothers, swathed in the black burqam robes that symbolize a traditional background role in Islamic life, caused headlines last month by protesting in public for tougher government action.
The next day children, many under age 10, took to the streets. Hundreds of parents signed a petition demanding the death sentence for peddlers.
''In an Islamic society, it's rather a remarkable thing for women to be so openly involved,'' says Dr. Zaheer Khan, who runs the country's only heroin treatment center at Civil Hospital in Karachi.
* Thousands of miles away, on the streets of Bogota, Colombia, the world's biggest exporter of cocaine, parents outraged at cocaine addiction among their children are telephoning the city police drug squad. They give the addresses of houses where cocaine bazucom is traded.
''And we go and raid those houses,'' affirms drug squad agent Clara Valencia Linares, who carries a gun in her shoulder bag and says she feels a special sense of mission to help families rid themselves of addiction.
Bogota agents say they have made 700 arrests in the last three months - but admit that the big bosses of the cocaine trade are still free and that corruption is rife. Some reports have tied cocaine involvement to members of the Columbian government.
* In The Hague, the Netherlands, Eddy Engelsman is secretary to a government committee now drafting special health education programs for schools which will give information about drug abuse, not to all pupils but only to those adjudged to be at risk - in areas of poverty and unemployment, for instance.
* In Hamburg, West Germany, Hans-Georg Behr, drug policy adviser for the Greens, is preparing a provocative package of legislation to be introduced into the Bundestag in the spring. It is designed to foster public discussion about Germany's fast-rising rates of heroin and cocaine addiction.
The package would remove criminal penalties for using drugs but would crack down on all trafficking. It would control ''precursor'' chemicals used to refine hard drugs (Germany provides 90 percent of all the acetic anhydride which is used around the world to refine morphine into heroin) and would sharply reduce tobacco, alcohol, and drug advertising.
* In four of the hundreds of steaming slums of Bangkok, Thailand, Dr. Udomsil Srisangnam of Mahidol University struggles to coordinate new health and prevention programs to reduce a soaring heroin addiction rate.
* In Singapore, harsh penalties imposed in 1975 (mandatory death sentences for anyone trafficking more than 15 grams of heroin or 30 grams of morphine) together with treatment programs, has led to government statements that the number of abusers have fallen from 13,000 in 1977 to about 6,000 today. Drug education is about to be included in primary school health programs and moral education courses in high schools.
* In London, the Ministry of Health is supporting new education approaches aimed at: (1) Teaching teachers how to tell school pupils about drugs; (2) Bringing together a variety of police, social workers, teachers, and others to map out education and prevention efforts; (3) Stressing to young people that life can be better and more rewarding without drugs. Social workers are being encouraged not to draw back from addicts and refer them to treatment centers, but to begin trying to help them find stable relationships with others, jobs, homes, etc.
Police, teachers, and health workers are paying attention to glue-sniffing in British high schools. It is not a crime, but it is seen as a gateway to harder drugs. In Avon, Bristol, police visit sniffers' homes, talk to parents, bring in social workers if necessary. Teachers are also involved.